Re: [tbench regression fixes]: digging out smelly deadmen.

From: Jiri Kosina
Date: Sun Oct 26 2008 - 15:04:02 EST


On Sun, 26 Oct 2008, Andrew Morton wrote:

> > > > 208.4 MB/sec -- vanilla 2.6.16.60
> > > > 201.6 MB/sec -- vanilla 2.6.20.1
> > > > 172.9 MB/sec -- vanilla 2.6.22.19
> > > > 74.2 MB/sec -- vanilla 2.6.23
> > > > 46.1 MB/sec -- vanilla 2.6.24.2
> > > > 30.6 MB/sec -- vanilla 2.6.26.1
> > > > I.e. huge drop for 2.6.23 (this was with default configs for each
> > > > respective kernel).
> Was this when we decreased the default value of
> /proc/sys/vm/dirty_ratio, perhaps? dbench is sensitive to that.

2.6.28 gives 41.8 MB/s with /proc/sys/vm/dirty_ratio == 50. So small
improvement, but still far far away from the throughput of pre-2.6.23
kernels.

--
Jiri Kosina
SUSE Labs
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/