From 3871b69ba1d5d795bbd0d479e982546c1e4c375f Mon Sep 17 00:00:00 2001 From: Tom Lane Date: Sun, 26 Mar 2000 07:04:54 +0000 Subject: [PATCH] Improve descriptions of postmaster switches. --- doc/src/sgml/ref/postmaster.sgml | 106 ++++++++++++++++++++------------------- 1 file changed, 54 insertions(+), 52 deletions(-) diff --git a/doc/src/sgml/ref/postmaster.sgml b/doc/src/sgml/ref/postmaster.sgml index f2f959ef39..958bcd3b3d 100644 --- a/doc/src/sgml/ref/postmaster.sgml +++ b/doc/src/sgml/ref/postmaster.sgml @@ -1,5 +1,5 @@ @@ -23,10 +23,9 @@ Postgres documentation 1999-07-20 -postmaster [ -B nBuffers ] [ -D DataDir ] [ -i ] [ -l ] -postmaster [ -B nBuffers ] [ -D DataDir ] [ -N nBackends ] [ -S ] - [ -d [ DebugLevel ] [ -i ] [ -l ] [ -o BackendOptions ] [ -p port ] -postmaster [ -n | -s ] ... +postmaster [ -B nBuffers ] [ -D DataDir ] [ -N maxBackends ] [ -S ] + [ -d DebugLevel ] [ -i ] [ -l ] + [ -o BackendOptions ] [ -p port ] [ -n | -s ] @@ -44,11 +43,11 @@ postmaster [ -n | -s ] ... -B nBuffers - The number of shared-memory buffers for the + Sets the number of shared-memory disk buffers for the postmaster - to allocate and manage for the backend server processes that it + to allocate for use by the backend server processes that it starts. This value defaults to 64 buffers, where each buffer is 8k bytes - (or whatever BLCKSZ is set to in config.h). + (or whatever BLCKSZ is set to in src/include/config.h). @@ -71,15 +70,17 @@ postmaster [ -n | -s ] ... - -N nBackends + -N maxBackends - The maximum number of backend server processes that this postmaster - is allowed to start. In the default configuration, this value - is usually set - to 32, and can be set as high as 1024 if your system will support that - many processes. Both the default and upper limit values can be altered - when building Postgres (see src/include/config.h). + Sets the maximum number of backend server processes that this postmaster + is allowed to start. By default, this value is 32, but it can be set + as high as 1024 if your system will support that many processes. + (Note that -B is required to be at least twice -N, so you'll need to + increase -B if you increase -N.) + Both the default and upper limit values for -N can be altered + when building Postgres + (see src/include/config.h). @@ -90,31 +91,34 @@ postmaster [ -n | -s ] ... Specifies that the postmaster process should start up in silent mode. That is, it will disassociate - from the user's (controlling) tty and start its own process group. - This should not be used in combination with debugging options because - any messages printed to standard output and standard error are - discarded. + from the user's (controlling) tty, start its own process group, and + redirect its standard output and standard error to + /dev/null. + + + Note that using this switch makes it very + difficult to troubleshoot problems, since all tracing and logging + output that would normally be generated by this postmaster and its + child backends will be discarded. - -d [ DebugLevel ] + -d DebugLevel - This argument DebugLevel - determines the amount of debugging output the backend servers will + Determines the amount of debugging output the backend servers will produce. If DebugLevel - is one, the postmaster will trace all connection traffic, - and nothing else. - For levels two and higher, - debugging is turned on in the backend process and the postmaster - displays more information, + is one, the postmaster will trace all connection traffic. + Levels two and higher turn on increasing amounts of debug output + from the backend processes, and the postmaster + displays more information including the backend environment and process traffic. - Note that if no file is specified for backend servers to - send their debugging output then this output will appear on the - controlling tty of their parent postmaster. + Note that unless the postmaster's standard output and standard error + are redirected into a log file, all this output will appear on the + controlling tty of the postmaster. @@ -123,9 +127,9 @@ postmaster [ -n | -s ] ... -i - This enables TCP/IP or Internet domain socket communication. - Without this option, only local Unix domain socket communication is - possible. + Allows clients to connect via TCP/IP (Internet domain) connections. + Without this option, only local Unix domain socket connections are + accepted. @@ -134,9 +138,9 @@ postmaster [ -n | -s ] ... -l - This enables SSL socket communication. The option + Enables secure connections using SSL. The option is also required. - You have to have compiled with SSL enabled to use this option. + You must have compiled with SSL enabled to use this option. @@ -147,7 +151,7 @@ postmaster [ -n | -s ] ... The postgres - options specified in + option(s) specified in BackendOptions are passed to all backend server processes started by this postmaster. @@ -180,8 +184,8 @@ postmaster [ -n | -s ] ... - A few command line options are available for debugging in the case - when a backend dies abnormally. + Two additional command line options are available for debugging problems + that cause a backend to die abnormally. These options control the behavior of the postmaster in this situation, and neither option is intended for use in @@ -204,10 +208,9 @@ postmaster [ -n | -s ] ... postmaster - will not reinitialize shared data structures. A knowledgable system - programmer can then use the - shmemdoc - program to examine shared memory and semaphore state. + will not reinitialize shared data structures. A knowledgeable system + programmer can then use a debugger + to examine shared memory and semaphore state. @@ -262,7 +265,7 @@ semget: No space left on device If you see this message, you should run the ipcclean - command. After doing this, try starting + command. After doing so, try starting postmaster again. If this still doesn't work, you probably need to configure your kernel for shared memory and semaphores as described in the @@ -277,7 +280,7 @@ semget: No space left on device You may be able to postpone reconfiguring your kernel by decreasing -B to reduce Postgres' shared memory - consumption, or by reducing -N to reduce Postgres' semaphore + consumption, and/or by reducing -N to reduce Postgres' semaphore consumption. @@ -291,10 +294,10 @@ StreamServerPort: cannot bind to port - If you see this message, you should be certain that there is no other - postmaster - process already running. The easiest way to determine this is by - using the command + If you see this message, you should make certain that there is no + other postmaster + process already running on the same port number. The easiest way to + determine this is by using the command % ps -ax | grep postmaster @@ -416,8 +419,8 @@ or its alternative form will prevent postmaster from freeing the system resources (e.g., shared memory and semaphores) - that it holds before dying. This prevents you from having to deal with - the problem with shared memory described earlier. + that it holds before dying. Use SIGTERM instead + to avoid having to clean up manually (as described earlier). @@ -450,8 +453,7 @@ or its alternative form - To start postmaster with a specific port - and executable name: + To start postmaster with a specific port: % nohup postmaster -p 1234 & -- 2.11.0