Re: Memory pressure handling with iSCSI

From: Badari Pulavarty
Date: Tue Jul 26 2005 - 17:51:44 EST


On Tue, 2005-07-26 at 15:10 -0700, Andrew Morton wrote:
> Badari Pulavarty <pbadari@xxxxxxxxxx> wrote:
> >
> > On Tue, 2005-07-26 at 14:24 -0700, Andrew Morton wrote:
> > > Badari Pulavarty <pbadari@xxxxxxxxxx> wrote:
> > > >
> > > > ext2 is incredibly better. Machine is very responsive.
> > > >
> > >
> > > OK. Please, always monitor and send /proc/meminfo. I assume that the
> > > dirty-memory clamping is working OK with ext2 and that perhaps it'll work
> > > OK with ext3/data=writeback.
> >
> > Nope. Dirty is still very high..
>
> That's a relief in a way. Can you please try decreasing the number of
> filesystems now?

Here is the data with 5 ext2 filesystems. I also collected /proc/meminfo
every 5 seconds. As you can see, we seem to dirty 6GB of data in 20
seconds of starting the test. I am not sure if its bad, since we have
lots of free memory..

Thanks,
Badari


procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu----
r b swpd free buff cache si so bi bo in cs us sy id wa
2 11 120 32912 10624 6813476 0 0 0 6766 10364 485 0 4 0 96
0 11 120 33036 10652 6813964 0 0 2 8889 10079 475 0 4 0 96
0 11 120 33036 10712 6813904 0 0 0 8077 9984 469 0 4 0 96
0 11 120 32912 10752 6814380 0 0 0 15576 10226 514 0 4 0 95
0 11 120 33036 10668 6813432 0 0 0 11334 10112 488 0 4 0 96
0 11 120 33656 10600 6813500 0 0 0 11811 10238 497 0 4 0 96
0 11 120 33036 10596 6814020 0 0 0 12713 10191 489 0 4 0 96
0 11 120 33036 10648 6813968 0 0 1 15775 10195 508 0 4 0 96
0 10 120 33780 10656 6812928 0 0 2 5390 10265 503 0 3 5 92
0 11 120 33036 10660 6813440 0 0 0 9700 10217 518 0 4 2 94


MemTotal: 7143628 kB
MemFree: 7001860 kB
Buffers: 5080 kB
Cached: 23300 kB
SwapCached: 0 kB
Active: 48600 kB
Inactive: 5872 kB
HighTotal: 0 kB
HighFree: 0 kB
LowTotal: 7143628 kB
LowFree: 7001860 kB
SwapTotal: 1048784 kB
SwapFree: 1048780 kB
Dirty: 0 kB
Writeback: 0 kB
Mapped: 45948 kB
Slab: 56348 kB
CommitLimit: 4620596 kB
Committed_AS: 148436 kB
PageTables: 1544 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 9888 kB
VmallocChunk: 34359728447 kB
HugePages_Total: 0
HugePages_Free: 0
Hugepagesize: 2048 kB

MemTotal: 7143628 kB
MemFree: 4871864 kB
Buffers: 14564 kB
Cached: 2091232 kB
SwapCached: 0 kB
Active: 51380 kB
Inactive: 2081780 kB
HighTotal: 0 kB
HighFree: 0 kB
LowTotal: 7143628 kB
LowFree: 4871864 kB
SwapTotal: 1048784 kB
SwapFree: 1048780 kB
Dirty: 2070752 kB
Writeback: 0 kB
Mapped: 46368 kB
Slab: 107912 kB
CommitLimit: 4620596 kB
Committed_AS: 148524 kB
PageTables: 1608 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 9888 kB
VmallocChunk: 34359728447 kB
HugePages_Total: 0
HugePages_Free: 0
Hugepagesize: 2048 kB

MemTotal: 7143628 kB
MemFree: 406384 kB
Buffers: 18940 kB
Cached: 6443960 kB
SwapCached: 0 kB
Active: 55688 kB
Inactive: 6435048 kB
HighTotal: 0 kB
HighFree: 0 kB
LowTotal: 7143628 kB
LowFree: 406384 kB
SwapTotal: 1048784 kB
SwapFree: 1048780 kB
Dirty: 6144652 kB
Writeback: 252152 kB
Mapped: 46380 kB
Slab: 216580 kB
CommitLimit: 4620596 kB
Committed_AS: 148756 kB
PageTables: 1608 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 9888 kB
VmallocChunk: 34359728447 kB
HugePages_Total: 0
HugePages_Free: 0
Hugepagesize: 2048 kB

MemTotal: 7143628 kB
MemFree: 32772 kB
Buffers: 10028 kB
Cached: 6817680 kB
SwapCached: 4 kB
Active: 48180 kB
Inactive: 6804552 kB
HighTotal: 0 kB
HighFree: 0 kB
LowTotal: 7143628 kB
LowFree: 32772 kB
SwapTotal: 1048784 kB
SwapFree: 1048664 kB
Dirty: 6489496 kB
Writeback: 285264 kB
Mapped: 46000 kB
Slab: 228172 kB
CommitLimit: 4620596 kB
Committed_AS: 148756 kB
PageTables: 1608 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 9888 kB
VmallocChunk: 34359728447 kB
HugePages_Total: 0
HugePages_Free: 0
Hugepagesize: 2048 kB

MemTotal: 7143628 kB
MemFree: 32524 kB
Buffers: 10056 kB
Cached: 6816620 kB
SwapCached: 4 kB
Active: 48672 kB
Inactive: 6803212 kB
HighTotal: 0 kB
HighFree: 0 kB
LowTotal: 7143628 kB
LowFree: 32524 kB
SwapTotal: 1048784 kB
SwapFree: 1048664 kB
Dirty: 6465124 kB
Writeback: 268876 kB
Mapped: 46008 kB
Slab: 229580 kB
CommitLimit: 4620596 kB
Committed_AS: 148996 kB
PageTables: 1608 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 9888 kB
VmallocChunk: 34359728447 kB
HugePages_Total: 0
HugePages_Free: 0
Hugepagesize: 2048 kB