linux/include
Mel Gorman 24b7e5819a mm: pagemap: avoid unnecessary overhead when tracepoints are deactivated
This was formerly the series "Improve sequential read throughput" which
noted some major differences in performance of tiobench since 3.0.
While there are a number of factors, two that dominated were the
introduction of the fair zone allocation policy and changes to CFQ.

The behaviour of fair zone allocation policy makes more sense than
tiobench as a benchmark and CFQ defaults were not changed due to
insufficient benchmarking.

This series is what's left.  It's one functional fix to the fair zone
allocation policy when used on NUMA machines and a reduction of overhead
in general.  tiobench was used for the comparison despite its flaws as
an IO benchmark as in this case we are primarily interested in the
overhead of page allocator and page reclaim activity.

On UMA, it makes little difference to overhead

          3.16.0-rc3   3.16.0-rc3
             vanilla lowercost-v5
User          383.61      386.77
System        403.83      401.74
Elapsed      5411.50     5413.11

On a 4-socket NUMA machine it's a bit more noticable

          3.16.0-rc3   3.16.0-rc3
             vanilla lowercost-v5
User          746.94      802.00
System      65336.22    40852.33
Elapsed     27553.52    27368.46

This patch (of 6):

The LRU insertion and activate tracepoints take PFN as a parameter
forcing the overhead to the caller.  Move the overhead to the tracepoint
fast-assign method to ensure the cost is only incurred when the
tracepoint is active.

Signed-off-by: Mel Gorman <mgorman@suse.de>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-08-06 18:01:20 -07:00
..
acpi acpi, apei, ghes: Factor out ioremap virtual memory for IRQ and NMI context. 2014-07-22 15:05:06 -07:00
asm-generic Char / Misc driver patches for 3.17-rc1 2014-08-04 17:32:24 -07:00
clocksource ARM: pxa: Add non device-tree timer link to clocksource 2014-07-23 12:02:39 +02:00
crypto Merge branch 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2014-08-06 08:06:39 -07:00
drm dma-buf: use reservation objects 2014-07-08 13:03:20 -07:00
dt-bindings USB patches for 3.17-rc1 2014-08-04 20:11:28 -07:00
keys Merge remote-tracking branch 'integrity/next-with-keys' into keys-next 2014-07-22 21:54:43 +01:00
kvm
linux mm/vmalloc.c: clean up map_vm_area third argument 2014-08-06 18:01:19 -07:00
math-emu
media [media] media: atmel-isi: add v4l2 async probe support 2014-07-30 19:35:06 -03:00
memory
misc
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-08-06 09:38:14 -07:00
pcmcia
ras trace, RAS: Add eMCA trace event interface 2014-06-25 13:26:47 -07:00
rdma
rxrpc
scsi SCSI for-linus on 20140705 2014-07-06 12:08:30 -07:00
sound ALSA: control: Protect user controls against concurrent access 2014-06-18 15:12:33 +02:00
target
trace mm: pagemap: avoid unnecessary overhead when tracepoints are deactivated 2014-08-06 18:01:20 -07:00
uapi Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2014-08-06 09:38:14 -07:00
video Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2014-06-12 11:32:30 -07:00
xen Merge branch 'x86-efi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-08-04 17:13:50 -07:00
Kbuild