summaryrefslogtreecommitdiff
path: root/Documentation/vm/zswap.txt
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2015-06-26 09:52:05 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2015-06-26 09:52:05 -0700
commit47a469421d792dcb91a1e73319d26134241953d2 (patch)
tree6a388381a434ebe87fed2fbb10a53ced7a7ce8b5 /Documentation/vm/zswap.txt
parentc13c81006314ad76c2b31824960a900385601b8b (diff)
parent51229b495340bd7a02ce3622d1966829b67054ea (diff)
Merge branch 'akpm' (patches from Andrew)
Merge second patchbomb from Andrew Morton: - most of the rest of MM - lots of misc things - procfs updates - printk feature work - updates to get_maintainer, MAINTAINERS, checkpatch - lib/ updates * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (96 commits) exit,stats: /* obey this comment */ coredump: add __printf attribute to cn_*printf functions coredump: use from_kuid/kgid when formatting corename fs/reiserfs: remove unneeded cast NILFS2: support NFSv2 export fs/befs/btree.c: remove unneeded initializations fs/minix: remove unneeded cast init/do_mounts.c: add create_dev() failure log kasan: remove duplicate definition of the macro KASAN_FREE_PAGE fs/efs: femove unneeded cast checkpatch: emit "NOTE: <types>" message only once after multiple files checkpatch: emit an error when there's a diff in a changelog checkpatch: validate MODULE_LICENSE content checkpatch: add multi-line handling for PREFER_ETHER_ADDR_COPY checkpatch: suggest using eth_zero_addr() and eth_broadcast_addr() checkpatch: fix processing of MEMSET issues checkpatch: suggest using ether_addr_equal*() checkpatch: avoid NOT_UNIFIED_DIFF errors on cover-letter.patch files checkpatch: remove local from codespell path checkpatch: add --showfile to allow input via pipe to show filenames ...
Diffstat (limited to 'Documentation/vm/zswap.txt')
-rw-r--r--Documentation/vm/zswap.txt18
1 files changed, 16 insertions, 2 deletions
diff --git a/Documentation/vm/zswap.txt b/Documentation/vm/zswap.txt
index 00c3d31e7971..8458c0861e4e 100644
--- a/Documentation/vm/zswap.txt
+++ b/Documentation/vm/zswap.txt
@@ -26,8 +26,22 @@ Zswap evicts pages from compressed cache on an LRU basis to the backing swap
device when the compressed pool reaches its size limit. This requirement had
been identified in prior community discussions.
-To enabled zswap, the "enabled" attribute must be set to 1 at boot time. e.g.
-zswap.enabled=1
+Zswap is disabled by default but can be enabled at boot time by setting
+the "enabled" attribute to 1 at boot time. ie: zswap.enabled=1. Zswap
+can also be enabled and disabled at runtime using the sysfs interface.
+An example command to enable zswap at runtime, assuming sysfs is mounted
+at /sys, is:
+
+echo 1 > /sys/modules/zswap/parameters/enabled
+
+When zswap is disabled at runtime it will stop storing pages that are
+being swapped out. However, it will _not_ immediately write out or fault
+back into memory all of the pages stored in the compressed pool. The
+pages stored in zswap will remain in the compressed pool until they are
+either invalidated or faulted back into memory. In order to force all
+pages out of the compressed pool, a swapoff on the swap device(s) will
+fault back into memory all swapped out pages, including those in the
+compressed pool.
Design: