From: Mark Wielaard <mark@klomp.org>
To: Stephen Crawley <crawley@dstc.edu.au>
Cc: Noa Resare <noa@resare.com>,
Mauve Discuss <mauve-discuss@sources.redhat.com>,
crawley@piglet.dstc.edu.au
Subject: Re: gnu/testlet/java/nio/channels/FileChannel/manyopen.java broken
Date: Fri, 08 Oct 2004 10:05:00 -0000 [thread overview]
Message-ID: <1097229925.1087.10.camel@localhost> (raw)
In-Reply-To: <200410080647.i986l9QQ020343@piglet.dstc.edu.au>
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Hi,
On Fri, 2004-10-08 at 08:47, Stephen Crawley wrote:
> noa@resare.com said:
> > Since the test doesn't actually test for anything other than the
> > ability to open many files and the extent of that ability isn't
> > specified in any spec that I'm aware of I suggest that we remove the
> > test.
>
> Agreed. It should be deleted.
>
> This testcase previously used to also (indirectly) check that orphaned file
> handles were closed by garbage collection finalization. However, this
> was done by explicitly calling System.gc(), and thus was even more broken
> that the current version of the testcase.
As the person that wrote this test let me explain why I wrote it and
what I think should be tested.
We had a problem with real programs that open lots of files quickly
(gjdoc does this for example, a jar tool or a webserver might be another
good example) and don't explicitly close these files, but let the
file/stream just get garbage collected since the program structure
doesn't explicitly define a "owner" for the file/stream object (which
isn't that uncommon since that is what you normally do with random
allocated objects, long life the garbage collector!).
What I think should be tested is whether a program can open lots of
files. And that the systems notices that stale file handle resources can
be removed so that a program can keep opening files if needed. (As long
as there are no large number of life file handles open at the same
time.)
Since I have seen multiple systems get this wrong in various ways I want
to have an explicit test for this situation. It might be that this test
does not simulate a real world program correctly, so if there are
alternatives I would like to hear them instead of just deleting the test
since some systems fail it.
Cheers,
Mark
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next prev parent reply other threads:[~2004-10-08 10:05 UTC|newest]
Thread overview: 7+ messages / expand[flat|nested] mbox.gz Atom feed top
2004-10-08 6:35 Noa Resare
2004-10-08 6:47 ` Stephen Crawley
2004-10-08 10:05 ` Mark Wielaard [this message]
2004-10-08 11:07 ` Noa Resare
2004-10-08 17:00 ` Thomas Zander
2004-10-11 0:50 ` Stephen Crawley
2004-10-11 6:39 Jeroen Frijters
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