Re: windows shared memory error

From: Andrew Dunstan <andrew(at)dunslane(dot)net>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: PostgreSQL-development <pgsql-hackers(at)postgresql(dot)org>
Subject: Re: windows shared memory error
Date: 2009-05-01 23:05:46
Message-ID: 49FB804A.2020001@dunslane.net
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Tom Lane wrote:
> Andrew Dunstan <andrew(at)dunslane(dot)net> writes:
>
>> We've seen similar things with other Windows file operations, IIRC. What
>> bothers me is that the problem might be precisely because the 1 second
>> sleep between the CloseHandle() call and the CreateFileMapping() call
>> might not be enough due to system load, so repeating the cycle without
>> increasing the sleep period will just repeat the error.
>>
>
> What system load? This is only called after all the backends are dead.
> And surely one CreateFileMapping syscall per second does not materially
> contribute to any load that is being caused by something else.
>
>
>

I didn't say Postgres was creating the load. In the case where this has
been happening for my client, there is an Apache server which can chew
up the machine mightily. I don't have any evidence that just repeating
the cycle a few times won't work, but neither do you have any that it
will, and I don't think the extra code complexity will be terribly
great. If it were more than a few extra lines I'd probably agree with you.

cheers

abdrew

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