On Fri, 2013-01-11 at 00:01 -0800, Andrew Morton wrote: > On Fri, 11 Jan 2013 12:46:15 +1100 paul.szabo@xxxxxxxxxxxxx wrote: > > > > ... I don't believe 64GB of RAM has _ever_ been booted on a 32-bit > > > kernel without either violating the ABI (3GB/1GB split) or doing > > > something that never got merged upstream ... > > > > Sorry to be so contradictory: > > > > psz@como:~$ uname -a > > Linux como.maths.usyd.edu.au 3.2.32-pk06.10-t01-i386 #1 SMP Sat Jan 5 18:34:25 EST 2013 i686 GNU/Linux > > psz@como:~$ free -l > > total used free shared buffers cached > > Mem: 64446900 4729292 59717608 0 15972 480520 > > Low: 375836 304400 71436 > > High: 64071064 4424892 59646172 > > -/+ buffers/cache: 4232800 60214100 > > Swap: 134217724 0 134217724 > > psz@como:~$ > > > > (though I would not know about violations). > > > > But OK, I take your point that I should move with the times. > > Check /proc/slabinfo, see if all your lowmem got eaten up by buffer_heads. > > If so, you *may* be able to work around this by setting > /proc/sys/vm/dirty_ratio really low, so the system keeps a minimum > amount of dirty pagecache around. Then, with luck, if we haven't > broken the buffer_heads_over_limit logic it in the past decade (we > probably have), the VM should be able to reclaim those buffer_heads. > > Alternatively, use a filesystem which doesn't attach buffer_heads to > dirty pages. xfs or btrfs, perhaps. > Hi Andrew, What's the meaning of attaching buffer_heads to dirty pages? > -- > To unsubscribe, send a message with 'unsubscribe linux-mm' in > the body to majordomo@xxxxxxxxx. For more info on Linux MM, > see: http://www.linux-mm.org/ . > Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a> -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>