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-rw-r--r--man5/proc.527
1 files changed, 27 insertions, 0 deletions
diff --git a/man5/proc.5 b/man5/proc.5
index eebebaeef4..351d684056 100644
--- a/man5/proc.5
+++ b/man5/proc.5
@@ -4887,6 +4887,33 @@ On some systems, it is not present.
This directory contains files for memory management tuning, buffer and
cache management.
.TP
+.IR /proc/sys/vm/admin_reserve_kbytes " (since Linux 3.10)"
+.\" commit 4eeab4f5580d11bffedc697684b91b0bca0d5009
+This file defines the amount of free memory (in KiB) on the system that
+that should be reserved for users with the capability
+.BR CAP_SYS_ADMIN .
+
+The default value in this file is the minimum of [3% of free pages, 8MiB]
+expressed as KiB.
+The default is intended to provide enough for the superuser
+to log in and kill a process, if necessary,
+under the default overcommit 'guess' mode (i.e., 0 in
+.IR /proc/sys/vm/overcommit_memory ).
+
+Systems running in "overcommit never" mode (i.e., 2 in
+.IR /proc/sys/vm/overcommit_memory )
+should increase the value in this file to account
+for the full virtual memory size of the programs used to recover (e.g.,
+.BR login (1)
+.BR ssh (1),
+and
+.BR top (1))
+Otherwise, the superuser may not be able to log in to recover the system.
+For example, on x86_64 a suitable value is 131072 (128MiB reserved).
+
+Changing the value in this file takes effect whenever
+an application requests memory.
+.TP
.IR /proc/sys/vm/compact_memory " (since Linux 2.6.35)"
When 1 is written to this file, all zones are compacted such that free
memory is available in contiguous blocks where possible.