[illumos-Advocates] RTI: 975 disable disksort for SSDs

[Garrett D'Amore]

garrett at thinkpad{27}> hg outgoing -v
running ssh anonhg at hg.illumos.org "hg -R illumos-gate serve --stdio"
remote: Not trusting file /export/illumos/hgrepos/illumos-gate/.hg/hgrc
from untrusted user hg, group hg
comparing with ssh://anonhg@hg.illumos.org/illumos-gate
searching for changes

changeset:   13360:c28d415b5009
tag:         tip
user:        Garrett D'Amore <garrett at nexenta.com>
date:        Mon May 02 12:32:04 2011 -0700

description:
	975 disable disksort for SSDs
	Reviewed by: Jason King <jason.brian.king at gmail.com>
	Reviewed by: Rich Lowe <richlowe at richlowe.net>
	Reviewed by: Adam Leventhal <ahl at delphix.com>
	Reviewed by: Dan McDonald <danmcd at nexenta.com>

modified:
   usr/src/uts/common/io/scsi/targets/sd.c


I've been running this for a few days on my laptop with these changes
using an SSD root drive, and while I don't have any quantitative
numbers, I haven't noticed any performance issues either.  One thing
I've done is verified that the change is effective using mdb to check
the sd state structures, and it is working properly.


hg pbchk is clean.

garrett at thinkpad{28}> hg pbchk
remote: Not trusting file /export/illumos/hgrepos/illumos-gate/.hg/hgrc
from untrusted user hg, group hg
remote: Not trusting file /export/illumos/hgrepos/illumos-gate/.hg/hgrc
from untrusted user hg, group hg
Copyright check:

C style check:

Header format check:

Java style check:

Mapfile comment check:

File permission check:

Keywords check:

Comments check:

Checking for new tags:

Checking for multiple heads (or branches):

Checking for branch changes:

Checking for uncommitted changes:

Checking for merges:

Nightly build mail:

garrett at thinkpad{29}> cat log/log.2011-04-30.19:44/mail_msg 

==== Nightly distributed build started:   Sat Apr 30 17:43:29 PDT 2011
====
==== Nightly distributed build completed: Sat Apr 30 19:44:51 PDT 2011
====

==== Total build time ====

real    2:01:22

==== Build environment ====

/usr/bin/uname
SunOS thinkpad 5.11 qlc2322 i86pc i386 i86pc

/opt/SUNWspro/bin/dmake
dmake: Sun Distributed Make 7.8 SunOS_i386 Patch 126504-01 2007/07/19
number of concurrent jobs = 10

32-bit compiler
/opt/onbld/bin/i386/cw -_cc
cw version 1.29
primary: /opt/SUNWspro/bin/cc
cc: Sun C 5.9 SunOS_i386 Patch 124868-10 2009/04/30
shadow: /usr/sfw/bin/gcc
gcc (GCC) 3.4.3 (csl-sol210-3_4-20050802)

64-bit compiler
/opt/onbld/bin/i386/cw -_cc
cw version 1.29
primary: /opt/SUNWspro/bin/cc
cc: Sun C 5.9 SunOS_i386 Patch 124868-10 2009/04/30
shadow: /usr/sfw/bin/gcc
gcc (GCC) 3.4.3 (csl-sol210-3_4-20050802)

/usr/java/bin/javac
java full version "1.6.0_21-b06"

/usr/ccs/bin/as
as: Sun Compiler Common 12 SunOS_i386 snv_121 08/03/2009

/usr/ccs/bin/ld
ld: Software Generation Utilities - Solaris Link Editors: 5.11-1.1726

Build project:  group.staff
Build taskid:   130

==== Nightly argument issues ====


==== Build version ====

disksort

==== Make clobber ERRORS ====


==== Make tools clobber ERRORS ====


==== Tools build errors ====


==== Build errors (DEBUG) ====


==== Build warnings (DEBUG) ====


==== Elapsed build time (DEBUG) ====

real  1:15:42.5
user  6:41:43.2
sys   1:18:52.9

==== Build noise differences (DEBUG) ====


==== package build errors (DEBUG) ====


==== Validating manifests against proto area ====


==== Check ELF runtime attributes ====


==== Diff ELF runtime attributes (since last build) ====


==== 'dmake lint' of src ERRORS ====


==== Elapsed time of 'dmake lint' of src ====

real    31:12.4
user  1:37:18.4
sys     57:12.9

==== lint warnings src ====


==== lint noise differences src ====


==== cstyle/hdrchk errors ====


==== Find core files ====


==== Check lists of files ====


==== Impact on file permissions ====