From 37df5da4d637fc8a8391aa85c775b14ba11a2c8c Mon Sep 17 00:00:00 2001 From: "baron@percona.com" <> Date: Tue, 31 Jan 2012 12:01:32 -0500 Subject: [PATCH] doc tweaks --- bin/pt-stalk | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) diff --git a/bin/pt-stalk b/bin/pt-stalk index b54f880e..355bf180 100755 --- a/bin/pt-stalk +++ b/bin/pt-stalk @@ -1257,7 +1257,8 @@ whether known or unknown, of using this tool. The two main categories of risks are those created by the nature of the tool (e.g. read-only tools vs. read-write tools) and those created by bugs. -pt-stalk is a read-only tool. It should be very low-risk. Some of the options +pt-stalk is a read-write tool; it collects data from the system and writes it +into a series of files. It should be very low-risk. Some of the options can cause intrusive data collection to be performed, however, so if you enable any non-default options, you should read their documentation carefully. @@ -1326,7 +1327,10 @@ resulting samples of data. Although this sounds simple enough, in practice there are a number of subtleties, such as detecting when the disk is beginning to fill up so that the -tool doesn't cause the server to run out of disk space. +tool doesn't cause the server to run out of disk space. This tool handles these +types of potential problems, so it's a good idea to use this tool instead of +writing something from scratch and possibly experiencing some of the hazards +this tool is designed to prevent. =head1 CONFIGURING @@ -1402,8 +1406,8 @@ first option on the command line. type: int; default: 5 The number of times the trigger condition must be true before collecting data. -This helps prevent false positives and make the trigger condition less -susceptible to firing when the condition recovers quickly. +This helps prevent false positives, and makes the trigger condition less likely +to fire when the problem recovers quickly. =item --daemonize @@ -1473,7 +1477,8 @@ L<"--variable"> column matches the L<"--match"> option. For example, to trigger when more than 10 processes are in the "statistics" state, use the following options: - --trigger processlist --variable State --match statistics --threshold 10 + --trigger processlist --variable State \ + --match statistics --threshold 10 =back @@ -1489,7 +1494,8 @@ simply sources the file and executes the function. For example, the function might look like the following: trg_plugin() { - mysql $EXT_ARGV -e "SHOW ENGINE INNODB STATUS" | grep -c "has waited at" + mysql $EXT_ARGV -e "SHOW ENGINE INNODB STATUS" \ + | grep -c "has waited at" } This snippet will count the number of mutex waits inside of InnoDB. It @@ -1597,7 +1603,7 @@ Print tool's version and exit. =head1 ENVIRONMENT -No env vars used. +This tool does not use any environment variables for configuration. =head1 SYSTEM REQUIREMENTS