Обсуждение: "effective_io_concurrency" cannot be changed error when starting 8.4.2 instance

Hi All;

I get the below error when trying to start an 8.4.2 instance

Anyone know what might be causing this?

FATAL:  parameter "effective_io_concurrency" cannot be changed


Thanks in advance

On Tue, Feb 9, 2010 at 1:00 AM, Kevin Kempter
<kevink@consistentstate.com> wrote:
> I get the below error when trying to start an 8.4.2 instance
>
> Anyone know what might be causing this?
>
> FATAL:  parameter "effective_io_concurrency" cannot be changed
>

What platform is this? Did you compile it yourself? What type of
system was it compiled on?

The error means that your system does not support the system interface
we need to support prefetching. In that case effective_io_concurrency
will be a read-only parameter set to 0 and any attempt to set it will
result in an error.



--
greg

Kevin Kempter <kevink@consistentstate.com> writes:
> I get the below error when trying to start an 8.4.2 instance
> Anyone know what might be causing this?

> FATAL:  parameter "effective_io_concurrency" cannot be changed

You're probably trying to set that on a platform that hasn't got the
necessary system calls to support it.

            regards, tom lane

Greg Stark <gsstark@mit.edu> writes:
> The error means that your system does not support the system interface
> we need to support prefetching. In that case effective_io_concurrency
> will be a read-only parameter set to 0 and any attempt to set it will
> result in an error.

I wonder whether it would be better to have it still be a read-write
parameter, but with min/max values equal to zero.  All the other cases
where we have read-only parameters, they're *always* read-only.  It
seems a bit odd that this one is platform-specific not only as to the
allowed range but whether it can be assigned at all.

            regards, tom lane