Re: swapping and the value of /proc/sys/vm/swappiness

Ray Bryant
2004-09-09T03:02:08Z

Marcelo,

For what it is worth, here are the benchmark results for the kernel with the
patch I discussed before, along with the previous 2.6.9-rc1-mm3 results:

Kernel Version 2.6.9-rc1-mm3:
Total I/O Avg Swap min max pg cache min max
----------- --------- ------- ------ --------- ------- -------
0 274.80 MB/s 10511 MB ( 5644, 14492) 13293 MB ( 8596, 17156)
20 267.02 MB/s 12624 MB ( 5578, 16287) 15298 MB ( 8468, 18889)
40 267.66 MB/s 13541 MB ( 6619, 17461) 16199 MB ( 9393, 20044)
60 233.73 MB/s 18094 MB ( 16550, 19676) 20629 MB ( 19103, 22192)
80 213.64 MB/s 20950 MB ( 15844, 22977) 23450 MB ( 18496, 25440)
100 164.58 MB/s 26004 MB ( 26004, 26004) 28410 MB ( 28327, 28455)

Kernel Version 2.6.9-rc1-mm3-kdb-nrmap:
Total I/O Avg Swap min max pg cache min max
----------- --------- ------- ------ --------- ------- -------
0 286.93 MB/s 7288 MB ( 4847, 14536) 10122 MB ( 7771, 17138)
20 252.43 MB/s 13305 MB ( 3950, 18337) 15938 MB ( 6866, 20876)
40 268.52 MB/s 11538 MB ( 5333, 17298) 14238 MB ( 8247, 19836)
60 242.72 MB/s 16367 MB ( 8652, 21217) 18909 MB ( 11514, 23561)
80 212.94 MB/s 19424 MB ( 5632, 24047) 21937 MB ( 8567, 26469)
100 161.66 MB/s 26006 MB ( 26004, 26007) 28445 MB ( 28407, 28471)

Except for the swappiness = 20 case, things are a smallish bit better for
the modified kernel than 2.6.9-rc1-mm3. Clearly we haven't found the root of
this problem yet.

Have you still been unable to duplicate this problem on a small i386 platform?
--
Best Regards,
Ray
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Ray Bryant
512-453-9679 (work) 512-507-7807 (cell)
raybry@sgi.com raybry@austin.rr.com
The box said: "Requires Windows 98 or better",
so I installed Linux.
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