StrategyDirtyBufferList wasn't being careful to honor max_buffers limit.

Bug is only latent given that sole caller is passing NBuffers, but it
could bite someone in the rear someday.

diff --git a/src/backend/storage/buffer/freelist.c b/src/backend/storage/buffer/freelist.c
index b4702e7ceb22c6374522053e473ecf7f903ad271..526d45d455f2d714bc54347177f501c6a91fba75 100644 (file)
--- a/src/backend/storage/buffer/freelist.c
+++ b/src/backend/storage/buffer/freelist.c
@@ -12,7 +12,7 @@
  *
  *
  * IDENTIFICATION
- *       $PostgreSQL: pgsql/src/backend/storage/buffer/freelist.c,v 1.44 2004/06/03 02:08:03 tgl Exp $
+ *       $PostgreSQL: pgsql/src/backend/storage/buffer/freelist.c,v 1.45 2004/06/11 17:20:39 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -709,6 +709,7 @@ StrategyInvalidateBuffer(BufferDesc *buf)
         */
        CLEAR_BUFFERTAG(buf->tag);
        buf->flags &= ~(BM_VALID | BM_DIRTY);
+       buf->cntxDirty = false;
        buf->bufNext = StrategyControl->listFreeBuffers;
        StrategyControl->listFreeBuffers = buf->buf_id;
 }
@@ -757,8 +758,7 @@ StrategyDirtyBufferList(BufferDesc **buffers, BufferTag *buftags,
        cdb_id_t1 = StrategyControl->listHead[STRAT_LIST_T1];
        cdb_id_t2 = StrategyControl->listHead[STRAT_LIST_T2];
 
-       while ((cdb_id_t1 >= 0 || cdb_id_t2 >= 0) && 
-                  num_buffer_dirty < max_buffers)
+       while (cdb_id_t1 >= 0 || cdb_id_t2 >= 0)
        {
                if (cdb_id_t1 >= 0)
                {
@@ -772,6 +772,8 @@ StrategyDirtyBufferList(BufferDesc **buffers, BufferTag *buftags,
                                        buffers[num_buffer_dirty] = buf;
                                        buftags[num_buffer_dirty] = buf->tag;
                                        num_buffer_dirty++;
+                                       if (num_buffer_dirty >= max_buffers)
+                                               break;
                                }
                        }
 
@@ -790,6 +792,8 @@ StrategyDirtyBufferList(BufferDesc **buffers, BufferTag *buftags,
                                        buffers[num_buffer_dirty] = buf;
                                        buftags[num_buffer_dirty] = buf->tag;
                                        num_buffer_dirty++;
+                                       if (num_buffer_dirty >= max_buffers)
+                                               break;
                                }
                        }