Messages in this thread |  | | | Date | Thu, 26 Mar 2009 17:11:48 -0700 | | From | Andrew Morton <> | | Subject | Re: Linux 2.6.29 |
| |
On Wed, 25 Mar 2009 16:23:08 -0700 (PDT) Linus Torvalds <torvalds@linux-foundation.org> wrote:
> > > On Wed, 25 Mar 2009, Theodore Tso wrote: > > > > > > The problem being that unlike the ratio, there's no sane default value > > > that you can at least argue is not _entirely_ pointless. > > > > Well, if the maximum time that someone wants to wait for an fsync() to > > return is one second, and the RAID array can write 100MB/sec > > How are you going to tell the kernel that the RAID array can write > 100MB/s? > > The kernel has no idea. >
userspace can do it quite easily. Run a self-tuning script after installation and when the disk hardware changes significantly.
It is very disappointing that nobody appears to have attempted to do _any_ sensible tuning of these controls in all this time - we just keep thrashing around trying to pick better magic numbers in the base kernel.
Maybe we should set the tunables to 99.9% to make it suck enough to motivate someone.
|  |