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Diffstat (limited to 'man/man1/pmdazswap.1')
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diff --git a/man/man1/pmdazswap.1 b/man/man1/pmdazswap.1 new file mode 100644 index 0000000..6a736dd --- /dev/null +++ b/man/man1/pmdazswap.1 @@ -0,0 +1,66 @@ +'\"macro stdmacro +.\" +.\" Copyright (c) 2014 Red Hat. +.\" +.\" This program is free software; you can redistribute it and/or modify it +.\" under the terms of the GNU General Public License as published by the +.\" Free Software Foundation; either version 2 of the License, or (at your +.\" option) any later version. +.\" +.\" This program is distributed in the hope that it will be useful, but +.\" WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY +.\" or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License +.\" for more details. +.\" +.\" +.TH PMDAZSWAP 1 "PCP" "Performance Co-Pilot" +.SH NAME +\f3pmdazswap\f1 \- zswap (compressed swap) PMDA +.SH DESCRIPTION +\f3pmdazswap\f1 is a Performance Metrics Domain Agent (PMDA) which exports +metric values about compressed swap operation, as tracked by the +.B zswap +Linux kernel module. +.PP +Zswap is a lightweight compressed cache for swap pages. +It takes pages that are in the process of being swapped out and attempts +to compress them into a dynamically allocated RAM-based memory pool. +Zswap trades CPU cycles for potentially reduced swap I/O. +This tradeoff can also result in a performance improvement if reads +from the compressed cache are faster than reads from a swap device. +.PP +This PMDA exports metrics about pool size, number of pages stored, and +various counters for the reasons pages are rejected. +.SH INSTALLATION +Install the zswap PMDA by using the Install script as root: +.PP + # cd $PCP_PMDAS_DIR/zswap +.br + # ./Install +.PP +To uninstall, do the following as root: +.PP + # cd $PCP_PMDAS_DIR/zswap +.br + # ./Remove +.PP +\fBpmdazswap\fR is launched by \fIpmcd\fR(1) and should never be executed +directly. The Install and Remove scripts notify \fIpmcd\fR(1) when the +agent is installed or removed. +.SH FILES +.IP "\fB$PCP_PMDAS_DIR/zswap/Install\fR" 4 +installation script for the \fBpmdazswap\fR agent +.IP "\fB$PCP_PMDAS_DIR/zswap/Remove\fR" 4 +undo installation script for the \fBpmdazswap\fR agent +.IP "\fB$PCP_LOG_DIR/pmcd/zswap.log\fR" 4 +default log file for error messages from \fBpmdazswap\fR +.SH PCP ENVIRONMENT +Environment variables with the prefix \fBPCP_\fR are used to parameterize +the file and directory names used by \fBPCP\fR. On each installation, the +file \fB/etc/pcp.conf\fR contains the local values for these variables. +The \fB$PCP_CONF\fR variable may be used to specify an alternative +configuration file, as described in \fIpcp.conf\fR(5). +.SH SEE ALSO +.BR pmcd (1) +and +.BR PCPIntro (1). |