Weird effects using BLOBs from libpq - Mailing list pgsql-general

From Joerg Hessdoerfer
Subject Weird effects using BLOBs from libpq
Date
Msg-id 5.0.0.25.0.20001019105122.00a763b0@192.168.0.1
Whole thread Raw
Responses Re: Weird effects using BLOBs from libpq  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-general
Hi!

I'm experiencing somewhat confusing results using lo_creat(), lo_open(),
lo_write()...

First effect I have noticed is that when I write more than a certain amount
of data
at once using lo_write(), my application hangs indefinitely (10K work
perfect, 100K not).
Is there a well-known limit? On what does it depend? Or is it an unexpected
feature ;-)

Next off, now that everything runs fine, it does so only when using a local
database - when
connecting over the network to our test server, i need to put in usleeps of
minimum 30ms
in between consecutive writes to the same BLOB - else writing fails and i
have to close
the DB connection to do anything useful with the DB again!

Now, that's what i call unexpected...

I'm afraid i can't give you source code right now, 'cause i'm using LabVIEW
(a graphical
programming language).

Oh, yes, the local DB is postgreSQL 7.0.2 on cygwin 1.1.4, cygipc 1.0.7.
The remote is
7.0.2 on RedHat 6.2, single CPU.

Any ideas what could cause these effects? Are they by design (shudder)?

Greetings,
    Joerg


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