From 888a214dc4c65e1486ef7d3ac6b0cf93ae3cc2c7 Mon Sep 17 00:00:00 2001 From: Stanislaw Gruszka <sgruszka@redhat.com> Date: Thu, 12 Jan 2012 17:17:39 -0800 Subject: [PATCH] slub: document setting min order with debug_guardpage_minorder > 0 Acked-by: David Rientjes <rientjes@google.com> Cc: Pekka Enberg <penberg@cs.helsinki.fi> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> --- Documentation/ABI/testing/sysfs-kernel-slab | 4 ++++ Documentation/vm/slub.txt | 5 ++++- 2 files changed, 8 insertions(+), 1 deletion(-) diff --git a/Documentation/ABI/testing/sysfs-kernel-slab b/Documentation/ABI/testing/sysfs-kernel-slab index 8b093f8222d31..91bd6ca5440f3 100644 --- a/Documentation/ABI/testing/sysfs-kernel-slab +++ b/Documentation/ABI/testing/sysfs-kernel-slab @@ -346,6 +346,10 @@ Description: number of objects per slab. If a slab cannot be allocated because of fragmentation, SLUB will retry with the minimum order possible depending on its characteristics. + When debug_guardpage_minorder=N (N > 0) parameter is specified + (see Documentation/kernel-parameters.txt), the minimum possible + order is used and this sysfs entry can not be used to change + the order at run time. What: /sys/kernel/slab/cache/order_fallback Date: April 2008 diff --git a/Documentation/vm/slub.txt b/Documentation/vm/slub.txt index 2acdda9601b09..6752870c4970d 100644 --- a/Documentation/vm/slub.txt +++ b/Documentation/vm/slub.txt @@ -131,7 +131,10 @@ slub_min_objects. slub_max_order specified the order at which slub_min_objects should no longer be checked. This is useful to avoid SLUB trying to generate super large order pages to fit slub_min_objects of a slab cache with -large object sizes into one high order page. +large object sizes into one high order page. Setting command line +parameter debug_guardpage_minorder=N (N > 0), forces setting +slub_max_order to 0, what cause minimum possible order of slabs +allocation. SLUB Debug output ----------------- -- GitLab