adulau/aha
1
0
Fork 0
mirror of https://github.com/adulau/aha.git synced 2024-12-27 19:26:25 +00:00
Code Issues Projects Releases Packages Wiki Activity

mm tracing: cleanup Documentation/trace/events-kmem.txt

Browse source 
Clean up typos/grammos/spellos in events-kmem.txt.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Randy Dunlap 2009-12-21 14:37:23 -08:00 committed by Linus Torvalds
parent a6cd13f3c9
commit 2ec91eec47
1 changed files with 7 additions and 7 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

14
Documentation/trace/events-kmem.txt
View file

@ -1,7 +1,7 @@
Subsystem Trace Points: kmem Subsystem Trace Points: kmem
The tracing system kmem captures events related to object and page allocation The kmem tracing system captures events related to object and page allocation
within the kernel. Broadly speaking there are four major subheadings. within the kernel. Broadly speaking there are five major subheadings.
o Slab allocation of small objects of unknown type (kmalloc) o Slab allocation of small objects of unknown type (kmalloc)
o Slab allocation of small objects of known type o Slab allocation of small objects of known type
@ -9,7 +9,7 @@ within the kernel. Broadly speaking there are four major subheadings.
o Per-CPU Allocator Activity o Per-CPU Allocator Activity
o External Fragmentation o External Fragmentation
This document will describe what each of the tracepoints are and why they This document describes what each of the tracepoints is and why they
might be useful. might be useful.
1. Slab allocation of small objects of unknown type 1. Slab allocation of small objects of unknown type
@ -34,7 +34,7 @@ kmem_cache_free call_site=%lx ptr=%p
These events are similar in usage to the kmalloc-related events except that These events are similar in usage to the kmalloc-related events except that
it is likely easier to pin the event down to a specific cache. At the time it is likely easier to pin the event down to a specific cache. At the time
of writing, no information is available on what slab is being allocated from, of writing, no information is available on what slab is being allocated from,
but the call_site can usually be used to extrapolate that information but the call_site can usually be used to extrapolate that information.
3. Page allocation 3. Page allocation
================== ==================
@ -80,9 +80,9 @@ event indicating whether it is for a percpu_refill or not.
When the per-CPU list is too full, a number of pages are freed, each one When the per-CPU list is too full, a number of pages are freed, each one
which triggers a mm_page_pcpu_drain event. which triggers a mm_page_pcpu_drain event.
The individual nature of the events are so that pages can be tracked The individual nature of the events is so that pages can be tracked
between allocation and freeing. A number of drain or refill pages that occur between allocation and freeing. A number of drain or refill pages that occur
consecutively imply the zone->lock being taken once. Large amounts of PCP consecutively imply the zone->lock being taken once. Large amounts of per-CPU
refills and drains could imply an imbalance between CPUs where too much work refills and drains could imply an imbalance between CPUs where too much work
is being concentrated in one place. It could also indicate that the per-CPU is being concentrated in one place. It could also indicate that the per-CPU
lists should be a larger size. Finally, large amounts of refills on one CPU lists should be a larger size. Finally, large amounts of refills on one CPU
@ -102,6 +102,6 @@ is important.
Large numbers of this event implies that memory is fragmenting and Large numbers of this event implies that memory is fragmenting and
high-order allocations will start failing at some time in the future. One high-order allocations will start failing at some time in the future. One
means of reducing the occurange of this event is to increase the size of means of reducing the occurrence of this event is to increase the size of
min_free_kbytes in increments of 3*pageblock_size*nr_online_nodes where min_free_kbytes in increments of 3*pageblock_size*nr_online_nodes where
pageblock_size is usually the size of the default hugepage size. pageblock_size is usually the size of the default hugepage size.