From: erik quanstrom <quanstro@quanstro.net>
To: 9fans@9fans.net
Subject: Re: [9fans] arm httpd
Date: Sun, 9 Nov 2014 15:21:24 -0500 [thread overview]
Message-ID: <09aeb45d6625e40fba13f98b078d9d8c@ladd.quanstro.net> (raw)
In-Reply-To: <075800B3-4D1C-42A6-96D3-41C4C93A4C35@corpus-callosum.com>
On Sun Nov 9 14:51:37 EST 2014, jas@corpus-callosum.com wrote:
>
> > On Nov 9, 2014, at 1:42 PM, erik quanstrom <quanstro@quanstro.net> wrote:
> >
> > the aside leads me to believe that there is something wrong with the segment
> > copy on fork. since the semaphore in question is in the data segment,
> > i'm going to guess that you're running the labs kernel, and you're hitting the
> > page caching issue we've seen before. does this happen on an atom kernel?
>
> Only happens in the labs ARM kernel. The labs mips and 386 kernels work fine
> in this situation.
my thinking is that this isn't a defect in the arch-specific bits but rather a timing
bug. in that case, only manifesting on certain hardware is not diagnostic.
do you have any reason to believe this is not a timing bug? it does fit the pattern
rarely seen on x86 systems. (actually (cf. the console appliance) there were ways
to really make x86 systems suffer by forking fast enough on slow hardware.)
- erik
next prev parent reply other threads:[~2014-11-09 20:21 UTC|newest]
Thread overview: 12+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-11-09 15:34 Jeff Sickel
2014-11-09 19:42 ` erik quanstrom
2014-11-09 19:51 ` Jeff Sickel
2014-11-09 20:21 ` erik quanstrom [this message]
2014-11-10 1:47 ` Jeff Sickel
2014-11-09 20:28 ` Skip Tavakkolian
-- strict thread matches above, loose matches on Subject: below --
2013-11-17 21:54 [9fans] arm & httpd Jeff Sickel
2013-11-17 22:04 ` Steve Simon
2013-11-17 22:33 ` Jeff Sickel
2013-11-17 23:40 ` erik quanstrom
2013-11-18 10:12 ` Richard Miller
2013-11-18 14:15 ` erik quanstrom
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