Re: port-alpha/35448

["Michael L. Hitch" <mhitch%lightning.msu.montana.edu@localhost>]

The following reply was made to PR port-alpha/35448; it has been noted by GNATS.

From: "Michael L. Hitch" <mhitch%lightning.msu.montana.edu@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: 
Subject: Re: port-alpha/35448
Date: Tue, 18 Dec 2012 08:54:58 -0700 (MST)

 On Mon, 17 Dec 2012, Aaron J. Grier wrote:
 
 > flogging a dead horse here, but figured it was time for an update.
 >
 > the RETREAT / ADVANCE patch in this PR definitely helped me with stability,
 > although this problem itself may be alpha-specific.
 
    As I remember, it only showed up with the alpha gcc, but did not seem to 
 be there for amd64 (I can't remember if I tried to check the sparc64 code 
 or not).
 
    I think the discussion about this change had someone not liking the 
 RETREAT/ADVANCE patch (or names) I had at the time.  I had thought about a 
 patch using a different macro name (ADJUSTUIO or something similar) so 
 that there was a single macro that would indicate the adjustment could go 
 either direction.  I've been a bit (!) negligent on following up on this.
 
 > the only idea I have for flushing out further bugs with the NFS
 > retransmit code would be pounding on a UDP mount over a lossy link, IE
 > purposely set mismatched duplex, crappy hub or switch, or a packet loss
 > simulator.
 
    I think (but it has been some time) I was able to replicate the problem 
 with just a cross-over link between my two CS20 machines.  Only one of 
 them is running at this time, so I'm not sure how easily I could 
 replicate it now.  Maybe that would be a good opportunity to power up my 
 1000A and update it.
 
 > since this patch does no harm and improves at least alpha, could it be
 > applied to current and pulled-up to NetBSD-6?
 
    I think NetBSD-6 has a newer version of gcc since then, and I would want 
 to verify that the patch is still needed before commiting anything.
 
 Mike
 
 
 --
 Michael L. Hitch                       mhitch%montana.edu@localhost
 Computer Consultant
 Information Technology Center
 Montana State University       Bozeman, MT     USA