randrianasulu at gmail.com
2010-Nov-15 15:40 UTC
[Nouveau] Different swap behaviour between 2.6.36 and .37-rc1 ?
Hello all.
I'm using this kernel tree:
http://cgit.freedesktop.org/nouveau/linux-2.6/
It works OK for most time, but some days ago i booted with mem=256m (machine
has 768mb of ram) and found what after merging 2.6.37-rc1 into this tree some
workloads generated much more swap activity, than 2.6.36-based tree (from
around 5/11/2010).
If I boot my kernel with mem=256m, then add swapfile (Adding 399996k swap
on /swap.file. Priority:-1 extents:728 across:2152040k) startx with nouveau
driver and start to do usual stuff, after some hours of use 2.6.37-rc1 based
kernel started to swap thing in and mostly OUT swapfile, sometimes stalling
machine for long time (around minute).
I have mozilla (seamonkey) session open most of time, in both cases it sized
around
14823 guest 20 0 298m 102m 11m S 10.5 41.5 156:43.55 seamonkey-bin
(~300 mb virt, ~100mb res)
Then, i start some git pull/make job (on wine or kernel source tree). After
job finished, 2.6.36-based kernel behave OK, even if i have some 126976k used
in swapfile. 2.6.37-rc1 based kernel starts to swap things, at application
start, at menu open time (e16 here - nothing over-bloated), when i scroll
some pages in seamonkey ... Most notable - closing seamonkey takes much more
time (and swap-outs) under 2.6.37-rc1 kernel.
May be this behaviour was fixed in latest mainline kernel, i tried to look
at /sys/class/drm/ttm/memory_accounting/kernel/used_memory but under both
kernel valus stays around 18000-19000 (currently: 18196) this lead me to thin
this is not just some pixmaps for my 256 Mb VRAM GeForce6200/agp videocard.
But i can be wrong here.
I have usual ide hdd, still configured as hdc/hdd:
/dev/hdd:
Model=SAMSUNG SP0802N, FwRev=TK200-04, SerialNo=S00JJ10X568638
Config={ HardSect NotMFM HdSw>15uSec Fixed DTR>10Mbs }
RawCHS=16383/16/63, TrkSize=34902, SectSize=554, ECCbytes=4
BuffType=DualPortCache, BuffSize=2048kB, MaxMultSect=16, MultSect=16
CurCHS=4047/16/255, CurSects=16511760, LBA=yes, LBAsects=156368016
IORDY=on/off, tPIO={min:240,w/IORDY:120}, tDMA={min:120,rec:120}
PIO modes: pio0 pio1 pio2 pio3 pio4
DMA modes: mdma0 mdma1 mdma2
UDMA modes: udma0 udma1 udma2 udma3 udma4 *udma5
AdvancedPM=no WriteCache=enabled
Drive conforms to: ATA/ATAPI-7 T13 1532D revision 0: ATA/ATAPI-1,2,3,4,5,6,7
* signifies the current active mode
/dev/hdc:
Model=ST3160021A, FwRev=8.01, SerialNo=5LJ0BXTG
Config={ HardSect NotMFM HdSw>15uSec Fixed DTR>10Mbs RotSpdTol>.5% }
RawCHS=16383/16/63, TrkSize=0, SectSize=0, ECCbytes=4
BuffType=unknown, BuffSize=2048kB, MaxMultSect=16, MultSect=16
CurCHS=4047/16/255, CurSects=16511760, LBA=yes, LBAsects=312581808
IORDY=on/off, tPIO={min:240,w/IORDY:120}, tDMA={min:120,rec:120}
PIO modes: pio0 pio1 pio2 pio3 pio4
DMA modes: mdma0 mdma1 mdma2
UDMA modes: udma0 udma1 udma2 udma3 udma4 *udma5
AdvancedPM=no WriteCache=enabled
Drive conforms to: ATA/ATAPI-6 T13 1410D revision 2: ATA/ATAPI-1,2,3,4,5,6
* signifies the current active mode
driver in use:
Uniform Multi-Platform E-IDE driver
via82cxxx 0000:00:11.1: VIA vt8233a (rev 00) IDE UDMA133
via82cxxx 0000:00:11.1: IDE controller (0x1106:0x0571 rev 0x06)
default ext3 with ordered data mode on all partitions touched by swap, make or
usual system activity (/ i mean).
/proc/sys/vm/swappines stays at 60 for two kernels, dirty_ratio - 20, constant
too.
I'm out of ideas what was changed, because i rebooted few times and 2.6.36
was
always better in this area, compared to 2.6.37-rc1. Note, you may need to
actually work with seamonkey , may be for few hours, right after session
restore it barely touches swap here with 256mb RAM.
I think i'll try until 2.6.37-rc2 and if this behaviour continued - I will
open bug at kernel bugzilla with configs and other data .....