Revision 6f5e6b9e69bf043074a0edabe3d271899c34eb79 authored by Hugh Dickins on 17 March 2006, 07:04:09 UTC, committed by Linus Torvalds on 17 March 2006, 15:51:26 UTC
Lee Revell reported 28ms latency when process with lots of swapped memory exits. 2.6.15 introduced a latency regression when unmapping: in accounting the zap_work latency breaker, pte_none counted 1, pte_present PAGE_SIZE, but a swap entry counted nothing at all. We think of pages present as the slow case, but Lee's trace shows that free_swap_and_cache's radix tree lookup can make a lot of work - and we could have been doing it many thousands of times without a latency break. Move the zap_work update up to account swap entries like pages present. This does account non-linear pte_file entries, and unmap_mapping_range skipping over swap entries, by the same amount even though they're quick: but neither of those cases deserves complicating the code (and they're treated no worse than they were in 2.6.14). Signed-off-by: Hugh Dickins <hugh@veritas.com> Acked-by: Nick Piggin <npiggin@suse.de> Acked-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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acorn | ||
acpi | ||
amba | ||
atm | ||
base | ||
block | ||
bluetooth | ||
cdrom | ||
char | ||
connector | ||
cpufreq | ||
crypto | ||
dio | ||
edac | ||
eisa | ||
fc4 | ||
firmware | ||
hwmon | ||
i2c | ||
ide | ||
ieee1394 | ||
infiniband | ||
input | ||
isdn | ||
macintosh | ||
mca | ||
md | ||
media | ||
message | ||
mfd | ||
misc | ||
mmc | ||
mtd | ||
net | ||
nubus | ||
oprofile | ||
parisc | ||
parport | ||
pci | ||
pcmcia | ||
pnp | ||
rapidio | ||
s390 | ||
sbus | ||
scsi | ||
serial | ||
sh | ||
sn | ||
spi | ||
tc | ||
telephony | ||
usb | ||
video | ||
w1 | ||
zorro | ||
Kconfig | -rw-r--r-- | 1.1 KB |
Makefile | -rw-r--r-- | 2.2 KB |
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