SVG: Pass only needed parameter instead of whole record_header

ust_time is the only needed parameter, used to determine the origin on
the X axis. So don't pass the pointer on the whole record_header
structure in svg_parm structure.

Signed-off-by: Sebastien GODARD <sysstat@users.noreply.github.com>

diff --git a/sa.h b/sa.h
index 5abc8e126a665d5f30077b3d57b0c4fa21b9cc78..e9476c3790d57010957cb8a4d6ad2c101956536a 100644 (file)
--- a/sa.h
+++ b/sa.h
@@ -282,9 +282,9 @@
 /* Structure for SVG specific parameters */
 struct svg_parm {
        unsigned long dt;
+       unsigned long ust_time_ref;
        int graph_no;
        int restart;
-       struct record_header *record_hdr;
 };
 
 

diff --git a/sadf.c b/sadf.c
index dfd7ccad77878c0a56ee80af4de86e1fdb32d74d..54e724bb077a0a044f36d5be01abc24a2f483709 100644 (file)
--- a/sadf.c
+++ b/sadf.c
@@ -886,7 +886,7 @@ void display_curr_act_graphs(int ifd, off_t fpos, int *curr, long *cnt, int *eos
        copy_structures(act, id_seq, record_hdr, !*curr, 2);
 
        parm.graph_no = *g_nr;
-       parm.record_hdr = &record_hdr[2];
+       parm.ust_time_ref = record_hdr[2].ust_time;
        parm.restart = TRUE;
 
        *cnt  = count;

diff --git a/svg_stats.c b/svg_stats.c
index c292314a97dbb6f593a569fb6322e605252ce223..7e08185507ea122325ffdb517de68649972485f8 100644 (file)
--- a/svg_stats.c
+++ b/svg_stats.c
@@ -626,8 +626,7 @@ void free_graphs(char **out, int *outsize, double *spmin, double *spmax)
  * @out                Pointer on array of chars for each graph definition.
  * @outsize    Size of array of chars for each graph definition.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no)
- *             and a pointer on a record header structure (.@record_hdr)
- *             containing the first stats sample.
+ *             and time used for the X axis origin (.@ust_time_ref).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
  */
@@ -682,7 +681,7 @@ void draw_activity_graphs(int g_nr, int g_type, char *title[], char *g_title[],
                 * At least two samples are needed.
                 * And a min and max value should have been found.
                 */
-               if ((record_hdr->ust_time == svg_p->record_hdr->ust_time) ||
+               if ((record_hdr->ust_time == svg_p->ust_time_ref) ||
                    (*(spmin + pos) == DBL_MAX) || (*(spmax + pos) == -DBL_MIN)) {
                        /* No data found */
                        printf("<text x=\"0\" y=\"%d\" style=\"fill: red; stroke: none\">No data</text>\n",
@@ -779,9 +778,9 @@ void draw_activity_graphs(int g_nr, int g_type, char *title[], char *g_title[],
                }
                while (ypos * j <= lmax);
 
-               k = xgrid(svg_p->record_hdr->ust_time, record_hdr->ust_time);
-               xfactor = (double) SVG_G_XSIZE / (record_hdr->ust_time - svg_p->record_hdr->ust_time);
-               stamp = *svg_p->record_hdr;
+               k = xgrid(svg_p->ust_time_ref, record_hdr->ust_time);
+               xfactor = (double) SVG_G_XSIZE / (record_hdr->ust_time - svg_p->ust_time_ref);
+               stamp.ust_time = svg_p->ust_time_ref; /* Only ust_time field needs to be set. TRUE_TIME not allowed */
                for (j = 0; (j <= SVG_V_GRIDNR) && (stamp.ust_time <= record_hdr->ust_time); j++) {
                        sa_get_record_timestamp_struct(flags, &stamp, &rectime, NULL);
                        set_record_timestamp_string(flags, &stamp, NULL, cur_time, 32, &rectime);
@@ -840,8 +839,8 @@ void draw_activity_graphs(int g_nr, int g_type, char *title[], char *g_title[],
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart), and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -937,7 +936,7 @@ __print_funct_t svg_print_cpu_stats(struct activity *a, int curr, int action, st
                                        }
 
                                        /* %idle */
-                                       cpuappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                                       cpuappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                                  &offset, val,
                                                  out + pos + j, outsize + pos + j, svg_p->dt,
                                                  spmin + pos + j, spmax + pos + j);
@@ -947,14 +946,14 @@ __print_funct_t svg_print_cpu_stats(struct activity *a, int curr, int action, st
 
                        if (DISPLAY_CPU_DEF(a->opt_flags)) {
                                /* %user */
-                               cpuappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                               cpuappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                          &offset, ll_sp_value(scp->cpu_user, scc->cpu_user, g_itv),
                                          out + pos, outsize + pos, svg_p->dt,
                                          spmin + pos, spmax + pos);
                        }
                        else {
                                /* %usr */
-                               cpuappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                               cpuappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                          &offset,
                                          (scc->cpu_user - scc->cpu_guest) < (scp->cpu_user - scp->cpu_guest) ?
                                           0.0 :
@@ -966,14 +965,14 @@ __print_funct_t svg_print_cpu_stats(struct activity *a, int curr, int action, st
 
                        if (DISPLAY_CPU_DEF(a->opt_flags)) {
                                /* %nice */
-                               cpuappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                               cpuappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                          &offset, ll_sp_value(scp->cpu_nice, scc->cpu_nice, g_itv),
                                          out + pos + 1, outsize + pos + 1, svg_p->dt,
                                          spmin + pos + 1, spmax + pos + 1);
                        }
                        else {
                                /* %nice */
-                               cpuappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                               cpuappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                          &offset,
                                          (scc->cpu_nice - scc->cpu_guest_nice) < (scp->cpu_nice - scp->cpu_guest_nice) ?
                                           0.0 :
@@ -985,7 +984,7 @@ __print_funct_t svg_print_cpu_stats(struct activity *a, int curr, int action, st
 
                        if (DISPLAY_CPU_DEF(a->opt_flags)) {
                                /* %system */
-                               cpuappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                               cpuappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                          &offset,
                                          ll_sp_value(scp->cpu_sys + scp->cpu_hardirq + scp->cpu_softirq,
                                                      scc->cpu_sys + scc->cpu_hardirq + scc->cpu_softirq,
@@ -995,45 +994,45 @@ __print_funct_t svg_print_cpu_stats(struct activity *a, int curr, int action, st
                        }
                        else {
                                /* %sys */
-                               cpuappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                               cpuappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                          &offset, ll_sp_value(scp->cpu_sys, scc->cpu_sys, g_itv),
                                          out + pos + 2, outsize + pos + 2, svg_p->dt,
                                          spmin + pos + 2, spmax + pos + 2);
                        }
 
                        /* %iowait */
-                       cpuappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                       cpuappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                  &offset, ll_sp_value(scp->cpu_iowait, scc->cpu_iowait, g_itv),
                                  out + pos + 3, outsize + pos + 3, svg_p->dt,
                                  spmin + pos + 3, spmax + pos + 3);
 
                        /* %steal */
-                       cpuappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                       cpuappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                  &offset, ll_sp_value(scp->cpu_steal, scc->cpu_steal, g_itv),
                                  out + pos + 4, outsize + pos + 4, svg_p->dt,
                                  spmin + pos + 4, spmax + pos + 4);
 
                        if (DISPLAY_CPU_ALL(a->opt_flags)) {
                                /* %irq */
-                               cpuappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                               cpuappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                          &offset, ll_sp_value(scp->cpu_hardirq, scc->cpu_hardirq, g_itv),
                                          out + pos + 5, outsize + pos + 5, svg_p->dt,
                                          spmin + pos + 5, spmax + pos + 5);
 
                                /* %soft */
-                               cpuappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                               cpuappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                          &offset, ll_sp_value(scp->cpu_softirq, scc->cpu_softirq, g_itv),
                                          out + pos + 6, outsize + pos + 6, svg_p->dt,
                                          spmin + pos + 6, spmax + pos + 6);
 
                                /* %guest */
-                               cpuappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                               cpuappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                          &offset, ll_sp_value(scp->cpu_guest, scc->cpu_guest, g_itv),
                                          out + pos + 7, outsize + pos + 7, svg_p->dt,
                                          spmin + pos + 7, spmax + pos + 7);
 
                                /* %gnice */
-                               cpuappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                               cpuappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                          &offset, ll_sp_value(scp->cpu_guest_nice, scc->cpu_guest_nice, g_itv),
                                          out + pos + 8, outsize + pos + 8, svg_p->dt,
                                          spmin + pos + 8, spmax + pos + 8);
@@ -1045,7 +1044,7 @@ __print_funct_t svg_print_cpu_stats(struct activity *a, int curr, int action, st
                        }
 
                        /* %idle */
-                       cpuappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                       cpuappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                  &offset,
                                  (scc->cpu_idle < scp->cpu_idle ? 0.0 :
                                   ll_sp_value(scp->cpu_idle, scc->cpu_idle, g_itv)),
@@ -1100,8 +1099,8 @@ __print_funct_t svg_print_cpu_stats(struct activity *a, int curr, int action, st
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -1133,11 +1132,11 @@ __print_funct_t svg_print_pcsw_stats(struct activity *a, int curr, int action, s
                save_extrema(1, 1, 0, (void *) a->buf[curr], (void *) a->buf[!curr],
                             itv, spmin, spmax);
                /* cswch/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(spp->context_switch, spc->context_switch, itv),
                         out, outsize, svg_p->restart);
                /* proc/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(spp->processes, spc->processes, itv),
                         out + 1, outsize + 1, svg_p->restart);
        }
@@ -1161,8 +1160,8 @@ __print_funct_t svg_print_pcsw_stats(struct activity *a, int curr, int action, s
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -1193,11 +1192,11 @@ __print_funct_t svg_print_swap_stats(struct activity *a, int curr, int action, s
                save_extrema(0, 2, 0, (void *) a->buf[curr], (void *) a->buf[!curr],
                             itv, spmin, spmax);
                /* pswpin/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(ssp->pswpin, ssc->pswpin, itv),
                         out, outsize, svg_p->restart);
                /* pswpout/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(ssp->pswpout, ssc->pswpout, itv),
                         out + 1, outsize + 1, svg_p->restart);
        }
@@ -1221,8 +1220,8 @@ __print_funct_t svg_print_swap_stats(struct activity *a, int curr, int action, s
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -1255,35 +1254,35 @@ __print_funct_t svg_print_paging_stats(struct activity *a, int curr, int action,
                save_extrema(0, 8, 0, (void *) a->buf[curr], (void *) a->buf[!curr],
                             itv, spmin, spmax);
                /* pgpgin/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(spp->pgpgin, spc->pgpgin, itv),
                         out, outsize, svg_p->restart);
                /* pgpgout/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(spp->pgpgout, spc->pgpgout, itv),
                         out + 1, outsize + 1, svg_p->restart);
                /* fault/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(spp->pgfault, spc->pgfault, itv),
                         out + 2, outsize + 2, svg_p->restart);
                /* majflt/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(spp->pgmajfault, spc->pgmajfault, itv),
                         out + 3, outsize + 3, svg_p->restart);
                /* pgfree/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(spp->pgfree, spc->pgfree, itv),
                         out + 4, outsize + 4, svg_p->restart);
                /* pgscank/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(spp->pgscan_kswapd, spc->pgscan_kswapd, itv),
                         out + 5, outsize + 5, svg_p->restart);
                /* pgscand/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(spp->pgscan_direct, spc->pgscan_direct, itv),
                         out + 6, outsize + 6, svg_p->restart);
                /* pgsteal/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(spp->pgsteal, spc->pgsteal, itv),
                         out + 7, outsize + 7, svg_p->restart);
        }
@@ -1307,8 +1306,8 @@ __print_funct_t svg_print_paging_stats(struct activity *a, int curr, int action,
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -1341,23 +1340,23 @@ __print_funct_t svg_print_io_stats(struct activity *a, int curr, int action, str
                             itv, spmin, spmax);
 
                /* tps */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(sip->dk_drive, sic->dk_drive, itv),
                         out, outsize, svg_p->restart);
                /* rtps */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(sip->dk_drive_rio,  sic->dk_drive_rio, itv),
                         out + 1, outsize + 1, svg_p->restart);
                /* wtps */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(sip->dk_drive_wio,  sic->dk_drive_wio, itv),
                         out + 2, outsize + 2, svg_p->restart);
                /* bread/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(sip->dk_drive_rblk, sic->dk_drive_rblk, itv),
                         out + 3, outsize + 3, svg_p->restart);
                /* bwrtn/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(sip->dk_drive_wblk, sic->dk_drive_wblk, itv),
                         out + 4, outsize + 4, svg_p->restart);
        }
@@ -1381,8 +1380,8 @@ __print_funct_t svg_print_io_stats(struct activity *a, int curr, int action, str
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -1480,89 +1479,89 @@ __print_funct_t svg_print_memory_stats(struct activity *a, int curr, int action,
                }
 
                /* MBmemfree */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         ((double) smc->frmkb) / 1024,
                         out, outsize, svg_p->restart);
                /* MBmemused */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         ((double) (smc->tlmkb - smc->frmkb)) / 1024,
                         out + 1, outsize + 1, svg_p->restart);
                /* MBcached */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         ((double) smc->camkb) / 1024,
                          out + 2, outsize + 2, svg_p->restart);
                /* MBbuffers */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         ((double) smc->bufkb) / 1024,
                         out + 3, outsize + 3, svg_p->restart);
                /* MBswpfree */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         ((double) smc->frskb) / 1024,
                         out + 4, outsize + 4, svg_p->restart);
                /* MBswpused */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         ((double) (smc->tlskb - smc->frskb)) / 1024,
                         out + 5, outsize + 5, svg_p->restart);
                /* MBswpcad */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         ((double) smc->caskb) / 1024,
                         out + 6, outsize + 6, svg_p->restart);
                /* MBcommit */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         ((double) smc->comkb) / 1024,
                         out + 7, outsize + 7, svg_p->restart);
                /* MBactive */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         ((double) smc->activekb) / 1024,
                         out + 8, outsize + 8, svg_p->restart);
                /* MBinact */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         ((double) smc->inactkb) / 1024,
                         out + 9, outsize + 9, svg_p->restart);
                /* MBdirty */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         ((double) smc->dirtykb) / 1024,
                         out + 10, outsize + 10, svg_p->restart);
                /* MBanonpg */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         ((double) smc->anonpgkb) / 1024,
                         out + 11, outsize + 11, svg_p->restart);
                /* MBslab */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         ((double) smc->slabkb) / 1024,
                         out + 12, outsize + 12, svg_p->restart);
                /* MBkstack */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         ((double) smc->kstackkb) / 1024,
                         out + 13, outsize + 13, svg_p->restart);
                /* MBpgtbl */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         ((double) smc->pgtblkb) / 1024,
                         out + 14, outsize + 14, svg_p->restart);
                /* MBvmused */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         ((double) smc->vmusedkb) / 1024,
                         out + 15, outsize + 15, svg_p->restart);
                /* %memused */
-               brappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               brappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         0.0,
                         smc->tlmkb ?
                         SP_VALUE(smc->frmkb, smc->tlmkb, smc->tlmkb) : 0.0,
                         out + 16, outsize + 16, svg_p->dt);
                /* %commit */
-               brappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               brappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         0.0,
                         (smc->tlmkb + smc->tlskb) ?
                         SP_VALUE(0, smc->comkb, smc->tlmkb + smc->tlskb) : 0.0,
                         out + 17, outsize + 17, svg_p->dt);
                /* %swpused */
-               brappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               brappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         0.0,
                         smc->tlskb ?
                         SP_VALUE(smc->frskb, smc->tlskb, smc->tlskb) : 0.0,
                         out + 18, outsize + 18, svg_p->dt);
                /* %swpcad */
-               brappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               brappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         0.0,
                         (smc->tlskb - smc->frskb) ?
                         SP_VALUE(0, smc->caskb, smc->tlskb - smc->frskb) : 0.0,
@@ -1620,8 +1619,8 @@ __print_funct_t svg_print_memory_stats(struct activity *a, int curr, int action,
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -1652,19 +1651,19 @@ __print_funct_t svg_print_ktables_stats(struct activity *a, int curr, int action
                save_extrema(0, 0, 4, (void *) a->buf[curr], NULL,
                             itv, spmin, spmax);
                /* file-nr */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) skc->file_used,
                          out, outsize, svg_p->restart);
                /* inode-nr */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) skc->inode_used,
                          out + 1, outsize + 1, svg_p->restart);
                /* dentunusd */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) skc->dentry_stat,
                          out + 2, outsize + 2, svg_p->restart);
                /* pty-nr */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) skc->pty_nr,
                          out + 3, outsize + 3, svg_p->restart);
        }
@@ -1688,8 +1687,8 @@ __print_funct_t svg_print_ktables_stats(struct activity *a, int curr, int action
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -1721,27 +1720,27 @@ __print_funct_t svg_print_queue_stats(struct activity *a, int curr, int action,
                save_extrema(0, 2, 4, (void *) a->buf[curr], NULL,
                             itv, spmin, spmax);
                /* runq-sz */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) sqc->nr_running,
                          out, outsize, svg_p->restart);
                /* blocked */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) sqc->procs_blocked,
                          out + 1, outsize + 1, svg_p->restart);
                /* ldavg-1 */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         (double) sqc->load_avg_1 / 100,
                         out + 2, outsize + 2, svg_p->restart);
                /* ldavg-5 */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         (double) sqc->load_avg_5 / 100,
                         out + 3, outsize + 3, svg_p->restart);
                /* ldavg-15 */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         (double) sqc->load_avg_15 / 100,
                         out + 4, outsize + 4, svg_p->restart);
                /* plist-sz */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) sqc->nr_threads,
                          out + 5, outsize + 5, svg_p->restart);
        }
@@ -1770,8 +1769,8 @@ __print_funct_t svg_print_queue_stats(struct activity *a, int curr, int action,
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -1884,42 +1883,42 @@ __print_funct_t svg_print_net_dev_stats(struct activity *a, int curr, int action
                        }
 
                        /* rxpck/s */
-                       lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                       lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                 S_VALUE(sndp->rx_packets, sndc->rx_packets, itv),
                                 out + pos, outsize + pos, restart);
 
                        /* txpck/s */
-                       lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                       lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                 S_VALUE(sndp->tx_packets, sndc->tx_packets, itv),
                                 out + pos + 1, outsize + pos + 1, restart);
 
                        /* rxkB/s */
-                       lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                       lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                 rxkb / 1024,
                                 out + pos + 2, outsize + pos + 2, restart);
 
                        /* txkB/s */
-                       lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                       lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                 txkb / 1024,
                                 out + pos + 3, outsize + pos + 3, restart);
 
                        /* rxcmp/s */
-                       lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                       lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                 S_VALUE(sndp->rx_compressed, sndc->rx_compressed, itv),
                                 out + pos + 4, outsize + pos + 4, restart);
 
                        /* txcmp/s */
-                       lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                       lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                 S_VALUE(sndp->tx_compressed, sndc->tx_compressed, itv),
                                 out + pos + 5, outsize + pos + 5, restart);
 
                        /* rxmcst/s */
-                       lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                       lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                 S_VALUE(sndp->multicast, sndc->multicast, itv),
                                 out + pos + 6, outsize + pos + 6, restart);
 
                        /* %ifutil */
-                       brappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                       brappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                 0.0, ifutil,
                                 out + pos + 7, outsize + pos + 7, svg_p->dt);
                }
@@ -1976,8 +1975,8 @@ __print_funct_t svg_print_net_dev_stats(struct activity *a, int curr, int action
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -2008,27 +2007,27 @@ __print_funct_t svg_print_net_sock_stats(struct activity *a, int curr, int actio
                save_extrema(0, 0, 6, (void *) a->buf[curr], NULL,
                             itv, spmin, spmax);
                /* totsck */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) snsc->sock_inuse,
                          out, outsize, svg_p->restart);
                /* tcpsck */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) snsc->tcp_inuse,
                          out + 1, outsize + 1, svg_p->restart);
                /* tcp-tw */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) snsc->tcp_tw,
                          out + 2, outsize + 2, svg_p->restart);
                /* udpsck */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) snsc->udp_inuse,
                          out + 3, outsize + 3, svg_p->restart);
                /* rawsck */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) snsc->raw_inuse,
                          out + 4, outsize + 4, svg_p->restart);
                /* ip-frag */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) snsc->frag_inuse,
                          out + 5, outsize + 5, svg_p->restart);
        }
@@ -2052,8 +2051,8 @@ __print_funct_t svg_print_net_sock_stats(struct activity *a, int curr, int actio
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -2087,35 +2086,35 @@ __print_funct_t svg_print_net_ip_stats(struct activity *a, int curr, int action,
                             itv, spmin, spmax);
 
                /* irec/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(snip->InReceives, snic->InReceives, itv),
                         out, outsize, svg_p->restart);
                /* fwddgm/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(snip->ForwDatagrams, snic->ForwDatagrams, itv),
                         out + 1, outsize + 1, svg_p->restart);
                /* idel/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(snip->InDelivers, snic->InDelivers, itv),
                         out + 2, outsize + 2, svg_p->restart);
                /* orq/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(snip->OutRequests, snic->OutRequests, itv),
                         out + 3, outsize + 3, svg_p->restart);
                /* asmrq/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(snip->ReasmReqds, snic->ReasmReqds, itv),
                         out + 4, outsize + 4, svg_p->restart);
                /* asmok/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(snip->ReasmOKs, snic->ReasmOKs, itv),
                         out + 5, outsize + 5, svg_p->restart);
                /* fragok/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(snip->FragOKs, snic->FragOKs, itv),
                         out + 6, outsize + 6, svg_p->restart);
                /* fragcrt/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(snip->FragCreates, snic->FragCreates, itv),
                         out + 7, outsize + 7, svg_p->restart);
        }
@@ -2139,8 +2138,8 @@ __print_funct_t svg_print_net_ip_stats(struct activity *a, int curr, int action,
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -2173,19 +2172,19 @@ __print_funct_t svg_print_net_tcp_stats(struct activity *a, int curr, int action
                             itv, spmin, spmax);
 
                /* active/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(sntp->ActiveOpens, sntc->ActiveOpens, itv),
                         out, outsize, svg_p->restart);
                /* passive/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(sntp->PassiveOpens, sntc->PassiveOpens, itv),
                         out + 1, outsize + 1, svg_p->restart);
                /* iseg/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(sntp->InSegs, sntc->InSegs, itv),
                         out + 2, outsize + 2, svg_p->restart);
                /* oseg/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(sntp->OutSegs, sntc->OutSegs, itv),
                         out + 3, outsize + 3, svg_p->restart);
        }
@@ -2209,8 +2208,8 @@ __print_funct_t svg_print_net_tcp_stats(struct activity *a, int curr, int action
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -2243,19 +2242,19 @@ __print_funct_t svg_print_net_udp_stats(struct activity *a, int curr, int action
                             itv, spmin, spmax);
 
                /* idgm/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(snup->InDatagrams, snuc->InDatagrams, itv),
                         out, outsize, svg_p->restart);
                /* odgm/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(snup->OutDatagrams, snuc->OutDatagrams, itv),
                         out + 1, outsize + 1, svg_p->restart);
                /* noport/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(snup->NoPorts, snuc->NoPorts, itv),
                         out + 2, outsize + 2, svg_p->restart);
                /* idgmerr/s */
-               lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         S_VALUE(snup->InErrors, snuc->InErrors, itv),
                         out + 3, outsize + 3, svg_p->restart);
        }
@@ -2279,8 +2278,8 @@ __print_funct_t svg_print_net_udp_stats(struct activity *a, int curr, int action
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -2310,19 +2309,19 @@ __print_funct_t svg_print_net_sock6_stats(struct activity *a, int curr, int acti
                save_extrema(0, 0, 4, (void *) a->buf[curr], NULL,
                             itv, spmin, spmax);
                /* tcp6sck */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) snsc->tcp6_inuse,
                          out, outsize, svg_p->restart);
                /* udp6sck */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) snsc->udp6_inuse,
                          out + 1, outsize + 1, svg_p->restart);
                /* raw6sck */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) snsc->raw6_inuse,
                          out + 2, outsize + 2, svg_p->restart);
                /* ip6-frag */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) snsc->frag6_inuse,
                          out + 3, outsize + 3, svg_p->restart);
        }
@@ -2346,8 +2345,8 @@ __print_funct_t svg_print_net_sock6_stats(struct activity *a, int curr, int acti
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -2386,7 +2385,7 @@ __print_funct_t svg_print_pwr_cpufreq_stats(struct activity *a, int curr, int ac
                                continue;
 
                        /* MHz */
-                       recappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                       recappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                  ((double) spp->cpufreq) / 100,
                                  ((double) spc->cpufreq) / 100,
                                  out + i, outsize + i, svg_p->restart, svg_p->dt,
@@ -2431,8 +2430,8 @@ __print_funct_t svg_print_pwr_cpufreq_stats(struct activity *a, int curr, int ac
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -2466,7 +2465,7 @@ __print_funct_t svg_print_pwr_fan_stats(struct activity *a, int curr, int action
                        spp = (struct stats_pwr_fan *) ((char *) a->buf[!curr]  + i * a->msize);
 
                        /* rpm */
-                       recappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                       recappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                  (double) spp->rpm,
                                  (double) spc->rpm,
                                  out + i, outsize + i, svg_p->restart, svg_p->dt,
@@ -2503,8 +2502,8 @@ __print_funct_t svg_print_pwr_fan_stats(struct activity *a, int curr, int action
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -2557,11 +2556,11 @@ __print_funct_t svg_print_pwr_temp_stats(struct activity *a, int curr, int actio
                        }
 
                        /* degC */
-                       lnappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                       lnappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                 (double) spc->temp,
                                 out + 2 * i, outsize + 2 * i, svg_p->restart);
                        /* %temp */
-                       brappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+                       brappend(record_hdr->ust_time - svg_p->ust_time_ref,
                                 0.0, tval,
                                 out + 2 * i + 1, outsize + 2 * i + 1, svg_p->dt);
                }
@@ -2601,8 +2600,8 @@ __print_funct_t svg_print_pwr_temp_stats(struct activity *a, int curr, int actio
  * @action     Action expected from current function.
  * @svg_p      SVG specific parameters: Current graph number (.@graph_no),
  *             flag indicating that a restart record has been previously
- *             found (.@restart) and a pointer on a record header structure
- *             (.@record_hdr) containing the first stats sample.
+ *             found (.@restart) and time used for the X axis origin
+ *             (@ust_time_ref).
  * @itv                Interval of time in jiffies (only with F_MAIN action).
  * @record_hdr Pointer on record header of current stats sample.
  ***************************************************************************
@@ -2651,15 +2650,15 @@ __print_funct_t svg_print_huge_stats(struct activity *a, int curr, int action, s
                }
 
                /* kbhugfree */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) smc->frhkb,
                          out, outsize, svg_p->restart);
                /* hugused */
-               lniappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               lniappend(record_hdr->ust_time - svg_p->ust_time_ref,
                          (unsigned long) smc->tlhkb - smc->frhkb,
                          out + 1, outsize + 1, svg_p->restart);
                /* %hugused */
-               brappend(record_hdr->ust_time - svg_p->record_hdr->ust_time,
+               brappend(record_hdr->ust_time - svg_p->ust_time_ref,
                         0.0, tval,
                         out + 2, outsize + 2, svg_p->dt);
        }