From: Andy Bavier <acb@cs.princeton.edu>
Date: Fri, 29 Oct 2004 18:17:34 +0000 (+0000)
Subject: README file
X-Git-Tag: pl_dod_0_2_15~2
X-Git-Url: http://git.onelab.eu/?p=mom.git;a=commitdiff_plain;h=af39fb4cc8ed8d40d5602486bcf3c29f0740f581

README file
---

diff --git a/README.txt b/README.txt
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+Overview
+--------
+
+"Pl_mom cleans up your mess" by resetting slices that are using up too
+much memory, and by rebooting the machine once the swap space is
+nearly full.
+
+Specifically, pl_mom takes the following actions based on the amount
+of consumed swap space:
+
+* at 85% full, pl_mom starts logging the available swap space to
+  syslogd
+
+* at 90% full, pl_mom resets the slice that is consuming the most
+  physical memory and sends an alert mail to that slice and the pl-mom
+  alias 
+
+* at 95% full, pl_mom reboots the machine and sends mail to the pl-mom
+  alias
+
+Pl_mom is organized as two processes.  The reboot process runs every
+second, and the slice reset process runs every 30 seconds.  The reboot
+process is very lightweight and only reads /proc/swaps.  However, the
+slice reset process may pull data from the slicestat sensor on port
+3100, which can potentially take a long time (on the order of minutes
+if there are thousands of processes on the machine).
+
+
+Building
+---------
+
+Rename the parent directory from pl_mom to pl_dod-0.2 (or whatever is
+the appropriate version number listed in the Makefile).  Then "make
+rpm" should do it.
+
+
+Notes
+------
+
+The name of the daemon is "pl_mom" but the package name is pl_dod.
+The reason is that the daemon and package were both originally called
+pl_dod.  Yum (the package management tool currently in use) does
+not seem to honor the "Obsoletes:" tag in the .spec file.  Therefore
+it was not possible to automatically update the old pl_dod package
+with a new one called pl_mom, and so the package kept the old name.