From: Bruce Momjian Date: Sun, 30 Jan 2005 04:00:19 +0000 (+0000) Subject: Remove FAQ items about IPC errors. We now report the help description X-Git-Tag: REL8_1_0BETA1~1459 X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=e136a49c5d8a7477793fd6f370746d1e794d1a18;p=postgresql Remove FAQ items about IPC errors. We now report the help description right in the failure. We can always re-add it if required. --- diff --git a/doc/FAQ b/doc/FAQ index c04ab44309..17fbde44fc 100644 --- a/doc/FAQ +++ b/doc/FAQ @@ -1,7 +1,7 @@ Frequently Asked Questions (FAQ) for PostgreSQL - Last updated: Sat Jan 29 22:51:43 EST 2005 + Last updated: Sat Jan 29 22:59:12 EST 2005 Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us) @@ -38,20 +38,14 @@ 3.1) How do I install PostgreSQL somewhere other than /usr/local/pgsql? - 3.2) When I start postmaster, I get a Bad System Call or core dumped - message. Why? - 3.3) When I try to start postmaster, I get IpcMemoryCreate errors. - Why? - 3.4) When I try to start postmaster, I get IpcSemaphoreCreate errors. - Why? - 3.5) How do I control connections from other hosts? - 3.6) How do I tune the database engine for better performance? - 3.7) What debugging features are available? - 3.8) Why do I get "Sorry, too many clients" when trying to connect? - 3.9) What is in the pgsql_tmp directory? - 3.10) Why do I need to do a dump and restore to upgrade PostgreSQL + 3.2) How do I control connections from other hosts? + 3.3) How do I tune the database engine for better performance? + 3.4) What debugging features are available? + 3.5) Why do I get "Sorry, too many clients" when trying to connect? + 3.6) What is in the pgsql_tmp directory? + 3.7) Why do I need to do a dump and restore to upgrade PostgreSQL releases? - 3.11) What computer hardware should I use? + 3.8) What computer hardware should I use? Operational Questions @@ -419,43 +413,7 @@ Specify the --prefix option when running configure. - 3.2) When I start postmaster, I get a Bad System Call or core dumped - message. Why? - - It could be a variety of problems, but first check to see that you - have System V extensions installed in your kernel. PostgreSQL requires - kernel support for shared memory and semaphores. - - 3.3) When I try to start postmaster, I get IpcMemoryCreate errors. Why? - - You either do not have shared memory configured properly in your - kernel or you need to enlarge the shared memory available in the - kernel. The exact amount you need depends on your architecture and how - many buffers and backend processes you configure for postmaster. For - most systems, with default numbers of buffers and processes, you need - a minimum of ~1 MB. See the PostgreSQL Administrator's Guide/Server - Run-time Environment/Managing Kernel Resources section for more - detailed information about shared memory and semaphores. - - 3.4) When I try to start postmaster, I get IpcSemaphoreCreate errors. Why? - - If the error message is IpcSemaphoreCreate: semget failed (No space - left on device) then your kernel is not configured with enough - semaphores. Postgres needs one semaphore per potential backend - process. A temporary solution is to start postmaster with a smaller - limit on the number of backend processes. Use -N with a parameter less - than the default of 32. A more permanent solution is to increase your - kernel's SEMMNS and SEMMNI parameters. - - Inoperative semaphores can also cause crashes during heavy database - access. - - If the error message is something else, you might not have semaphore - support configured in your kernel at all. See the PostgreSQL - Administrator's Guide for more detailed information about shared - memory and semaphores. - - 3.5) How do I control connections from other hosts? + 3.2) How do I control connections from other hosts? By default, PostgreSQL only allows connections from the local machine using Unix domain sockets or TCP/IP connections. Other machines will @@ -463,7 +421,7 @@ postgresql.conf and enable host-based authentication by modifying the file $PGDATA/pg_hba.conf accordingly. - 3.6) How do I tune the database engine for better performance? + 3.3) How do I tune the database engine for better performance? Certainly, indexes can speed up queries. The EXPLAIN ANALYZE command allows you to see how PostgreSQL is interpreting your query, and which @@ -495,7 +453,7 @@ You can also use the CLUSTER command to group data in tables to match an index. See the CLUSTER manual page for more details. - 3.7) What debugging features are available? + 3.4) What debugging features are available? PostgreSQL has several features that report status information that can be valuable for debugging purposes. @@ -550,7 +508,7 @@ log_* in the client's current directory. Linux requires a compile with -DLINUX_PROFILE for proper profiling. - 3.8) Why do I get "Sorry, too many clients" when trying to connect? + 3.5) Why do I get "Sorry, too many clients" when trying to connect? You need to increase postmaster's limit on how many concurrent backend processes it can start. @@ -570,7 +528,7 @@ log_* that PostgreSQL has a limit on the number of allowed backend processes is so your system won't run out of resources. - 3.9) What is in the pgsql_tmp directory? + 3.6) What is in the pgsql_tmp directory? This directory contains temporary files generated by the query executor. For example, if a sort needs to be done to satisfy an ORDER @@ -581,7 +539,7 @@ log_* remain if a backend crashes during a sort. A stop and restart of the postmaster will remove files from those directories. - 3.10) Why do I need to do a dump and restore to upgrade between major + 3.7) Why do I need to do a dump and restore to upgrade between major PostgreSQL releases? The PostgreSQL team makes only small changes between minor releases, @@ -596,7 +554,7 @@ log_* script can be used to upgrade without a dump/restore. The release notes mention whether pg_upgrade is available for the release. - 3.11) What computer hardware should I use? + 3.8) What computer hardware should I use? Because PC hardware is mostly compatible, people tend to believe that all PC hardware is of equal quality. It is not. ECC RAM, SCSI, and diff --git a/doc/src/FAQ/FAQ.html b/doc/src/FAQ/FAQ.html index 797b708f8f..b7e62d9f1f 100644 --- a/doc/src/FAQ/FAQ.html +++ b/doc/src/FAQ/FAQ.html @@ -10,7 +10,7 @@ alink="#0000ff">

Frequently Asked Questions (FAQ) for PostgreSQL

-

Last updated: Sat Jan 29 22:51:43 EST 2005

+

Last updated: Sat Jan 29 22:59:12 EST 2005

Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us)
@@ -56,24 +56,18 @@

Administrative Questions

3.1) How do I install PostgreSQL somewhere other than /usr/local/pgsql?
- 3.2) When I start postmaster, I get a - Bad System Call or core dumped message. Why?
- 3.3) When I try to start postmaster, I - get IpcMemoryCreate errors. Why?
- 3.4) When I try to start postmaster, I - get IpcSemaphoreCreate errors. Why?
- 3.5) How do I control connections from other + 3.2) How do I control connections from other hosts?
- 3.6) How do I tune the database engine for + 3.3) How do I tune the database engine for better performance?
- 3.7) What debugging features are available?
- 3.8) Why do I get "Sorry, too many + 3.4) What debugging features are available?
+ 3.5) Why do I get "Sorry, too many clients" when trying to connect?
- 3.9) What is in the pgsql_tmp + 3.6) What is in the pgsql_tmp directory?
- 3.10) Why do I need to do a dump and restore + 3.7) Why do I need to do a dump and restore to upgrade PostgreSQL releases?
- 3.11) What computer hardware should I use?
+ 3.8) What computer hardware should I use?

Operational Questions

@@ -544,47 +538,7 @@

Specify the --prefix option when running configure.

-

3.2) When I start postmaster, I get a - Bad System Call or core dumped message. Why?

- -

It could be a variety of problems, but first check to see that - you have System V extensions installed in your kernel. PostgreSQL - requires kernel support for shared memory and semaphores.

- -

3.3) When I try to start postmaster, I - get IpcMemoryCreate errors. Why?

- -

You either do not have shared memory configured properly in your - kernel or you need to enlarge the shared memory available in the - kernel. The exact amount you need depends on your architecture and - how many buffers and backend processes you configure for - postmaster. For most systems, with default numbers of - buffers and processes, you need a minimum of ~1 MB. See the PostgreSQL - Administrator's Guide/Server Run-time Environment/Managing Kernel Resources - section for more detailed information about shared memory and semaphores.

- -

3.4) When I try to start postmaster, I - get IpcSemaphoreCreate errors. Why?

- -

If the error message is IpcSemaphoreCreate: semget failed (No - space left on device) then your kernel is not configured with - enough semaphores. Postgres needs one semaphore per potential - backend process. A temporary solution is to start postmaster - with a smaller limit on the number of backend processes. Use - -N with a parameter less than the default of 32. A more - permanent solution is to increase your kernel's - SEMMNS and SEMMNI parameters.

- -

Inoperative semaphores can also cause crashes during heavy - database access.

- -

If the error message is something else, you might not have - semaphore support configured in your kernel at all. See the - PostgreSQL Administrator's Guide for more detailed information - about shared memory and semaphores.

- -

3.5) How do I control connections from other +

3.2) How do I control connections from other hosts?

By default, PostgreSQL only allows connections from the local @@ -594,7 +548,7 @@ host-based authentication by modifying the file $PGDATA/pg_hba.conf accordingly.

-

3.6) How do I tune the database engine for +

3.3) How do I tune the database engine for better performance?

Certainly, indexes can speed up queries. The @@ -633,7 +587,7 @@ data in tables to match an index. See the CLUSTER manual page for more details.

-

3.7) What debugging features are +

3.4) What debugging features are available?

PostgreSQL has several features that report status information @@ -691,7 +645,7 @@ file will be put in the client's current directory. Linux requires a compile with -DLINUX_PROFILE for proper profiling.

-

3.8) Why do I get "Sorry, too many +

3.5) Why do I get "Sorry, too many clients" when trying to connect?

You need to increase postmaster's limit on how many @@ -716,7 +670,7 @@ the number of allowed backend processes is so your system won't run out of resources.

-

3.9) What is in the pgsql_tmp directory?

+

3.6) What is in the pgsql_tmp directory?

This directory contains temporary files generated by the query executor. For example, if a sort needs to be done to satisfy an @@ -728,7 +682,7 @@ remain if a backend crashes during a sort. A stop and restart of the postmaster will remove files from those directories.

-

3.10) Why do I need to do a dump and restore +

3.7) Why do I need to do a dump and restore to upgrade between major PostgreSQL releases?

The PostgreSQL team makes only small changes between minor releases, @@ -744,7 +698,7 @@ The release notes mention whether pg_upgrade is available for the release.

-

3.11) What computer hardware should I use?

+

3.8) What computer hardware should I use?

Because PC hardware is mostly compatible, people tend to believe that all PC hardware is of equal quality. It is not. ECC RAM, SCSI, and