On Fri, 21 Jan 2000, Alan Cox wrote:
>> The bank gives us 32 pages of credit. We don't need to get the I/O on
>> them. We have a credit that we can use to optimze the I/O.
>
>32 pages, thats 87 ethernet packets. At 100Mbit thats a rather short period
>of time. I make it 1/60th of a second
Actually the 32 pages I was talking about aren't the freepages.min but the
SWAP_CUSTER_MAX.
Anyway I think to see the problem described by Rik and actually I think it
can be fixed by killing the useless polling of 1 second and replacing it
with an unconiditional pre-wakeup of kswapd when GFP touch the
freepages.high watermark. This will in turn should also help performances
and it will try to free the cache from inside kswapd before a process have
to free it itself.
I said "useless polling" exactly because of what you said, that is a
network allocation will eat the freepages.min pages in less than 1 second.
Andrea
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.rutgers.edu
Please read the FAQ at http://www.tux.org/lkml/
This archive was generated by hypermail 2b29 : Sun Jan 23 2000 - 21:00:24 EST