Thread: bigger blob rows?

bigger blob rows?

From
Eric Davies
Date:
Back in the days of 7.4.2, we tried storing large blobs  (1GB+) in postgres but found them too slow because the blob was being chopped into 2K rows stored in some other table.
However, it has occurred to us that if it was possible to configure the server to split blobs into bigger pieces, say 32K,  our speed problems might diminish correspondingly.
Is there a compile time constant or a run time configuration entry that accomplish this?

Thank you.

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Eric Davies, M.Sc.
Barrodale Computing Services Ltd.
Tel: (250) 472-4372 Fax: (250) 472-4373
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Email: eric@barrodale.com
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Re: bigger blob rows?

From
Doug McNaught
Date:
Eric Davies <Eric@barrodale.com> writes:

>    Back in the days of 7.4.2, we tried storing large blobs  (1GB+) in
>    postgres but found them too slow because the blob was being chopped
>    into 2K rows stored in some other table.
>    However, it has occurred to us that if it was possible to configure
>    the server to split blobs into bigger pieces, say 32K,  our speed
>    problems might diminish correspondingly.
>    Is there a compile time constant or a run time configuration entry
>    that accomplish this?

I *think* the limit would be 8k (the size of a PG page) even if you
could change it.  Upping that would require recompiling with PAGE_SIZE
set larger, which would have a lot of other consequences.

-Doug

Re: bigger blob rows?

From
Volkan YAZICI
Date:
On Jan 18 09:00, Eric Davies wrote:
> Back in the days of 7.4.2, we tried storing large blobs  (1GB+) in
> postgres but found them too slow because the blob was being chopped
> into 2K rows stored in some other table.
> However, it has occurred to us that if it was possible to configure
> the server to split blobs into bigger pieces, say 32K,  our speed
> problems might diminish correspondingly.
> Is there a compile time constant or a run time configuration entry
> that accomplish this?

include/storage/large_object.h:64: #define LOBLKSIZE       (BLCKSZ / 4)
include/pg_config_manual.h:26: #define BLCKSZ  8192


HTH.
Regards.