Re: kern/37025: mount_smbfs write performance is <censored>

[David Holland <dholland-bugs%netbsd.org@localhost>]

The following reply was made to PR kern/37025; it has been noted by GNATS.

From: David Holland <dholland-bugs%netbsd.org@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: kern/37025: mount_smbfs write performance is <censored>
Date: Mon, 1 Mar 2010 03:03:19 +0000

 (sent to gnats instead of gnats-bugs)
 
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 From: "Martin S. Weber" <Ephaeton%gmx.net@localhost>
 To: NetBSD Problem Report DB Administrator <gnats%NetBSD.org@localhost>
 Subject: kern/37025
 Date: Sat, 27 Feb 2010 00:17:03 -0500
 
 Fwiw, I started my first measurements finally. As I've noted before, there's
 some unrelated problems I'm facing, which should be fixed this way or another.
 I probably should open separate PRs for them:
 - a process in smbwrq often cannot be killed (even with -9) before the WHOLE
   writing is done.
 - sometimes transfers stall. I have to cd in the dir in question (hmm or 
somewhere
   on the mounted share?) and/or do an ls in that directory to get the transfer
   to pick up pace again.
 
 First results show that (not surprisingly I guess (even though I reported
 this BEFORE 4.0 :p)) NetBSD-5.0's kernel-backed mount_smbfs performs
 old-school:  putting packets on horse back, exchanging horses at a couple of
 stations and losing some of them. Performance peaks at about 1.5MiB/s, but
 at times is as low as 600KiB/s - smbclient works at the network maximum.
 Another observation (via xosview's NET display) is that smbclient uses a lot
 less sent packets when reading from the share in contrast to mount_smbfs.
 Some earlier observation in this PR, that more RTT suffering comes into play
 with the native mount, seems to be backed up by this observation. I still
 have some things to do here, especially measure -current, and probably other
 means of getting a file onto the samba share; measure the RTT to see if you
 can relate it to the results; probably some netstat stats for mount_smbfs
 vs. smbclient vs. -current (if that is performing any better, which I doubt:
 why should it now, after a few months, have been improved, if it hasn't for
 ALL THESE YEARS before).
 
 Stay tuned...
 -Martin