Re: [PATCH 2/4] fastboot: make scsi probes asynchronous

Arjan van de Ven
2009-01-04T18:13:53Z

On Sun, 4 Jan 2009 11:05:15 -0700
Matthew Wilcox <matthew@wil.cx> wrote:

> On Sun, Jan 04, 2009 at 09:29:40AM -0800, Arjan van de Ven wrote:
> > >From 2087b546abddced50fa73ea9a71b5a040ae1026e Mon Sep 17 00:00:00
> > >2001
> > From: Arjan van de Ven <arjan@linux.intel.com>
> > Date: Sun, 4 Jan 2009 05:32:28 -0800
> > Subject: [PATCH] fastboot: make scsi probes asynchronous
> >
> > This patch makes part of the scsi probe (which is mostly device
> > spin up and the partition scan) asynchronous. Only the part that
> > runs after getting the device number allocated is asynchronous,
> > ensuring that device numbering remains stable.
>
> Is this really a big win? Were you using the async scsi scan code
> already?

just checked;
my box has CONFIG_SCSI_SCAN_ASYNC=y set for both cases
it seems to be about 0.1 seconds win still though...
sounds little, but a kernel boot should be less than a second, so that
is still 10%. And it's obviously also disk dependent..
(I used libata connected disks obviously)

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