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Thread: Could not receive data from server

Could not receive data from server

From
Amin Abdulghani
Date:
Hi,

Running Postgres 7.2.1 with python/psycopg (python
interface for postgres using libpq)/webware application
server on Solaris, I get a postgres error "could not
receive data from server Error 0 " when I try to retrieve
a large text column (16 K) from a table. The query I use
is "select col from table". However, if I avoid the
webware application server, this seems to work ok. I am
just wondering what effect webware could have on the
postgres client libraries. The postgres server is on a
different machine. It doesnt seem to be a memory related
issue as web-ware uses only 5-6 MB on a machine having 256
MB.

Thanks..
Amin

Re: Could not receive data from server

From
Tom Lane
Date:
Amin Abdulghani <amin@quantiva.com> writes:
> Running Postgres 7.2.1 with python/psycopg (python
> interface for postgres using libpq)/webware application
> server on Solaris, I get a postgres error "could not
> receive data from server Error 0 " when I try to retrieve
> a large text column (16 K) from a table.

Hmm, are you using an SSL-encrypted connection?  If so, does it happen
when you don't encrypt?  We recently found several bugs in the 7.3
version of the SSL interface code, but since it had been largely
rewritten since 7.2, I didn't look to see if the bugs might apply to
7.2.

            regards, tom lane

Re: Could not receive data from server

From
Amin Abdulghani
Date:
Compiling postgres client with -D_REENTRANT seems to
remove
this problem. It seems to have been a thread issue with
webware (and more specfically errno associated the
pqReadData).
On a side note, I noticed that the configure.in for 7.2.1
doesnt seem to have any option for compiling with the
above flag. Is it available for the next releases 7.3/7.4?

Thanks..
Amin
On Tue, 05 Aug 2003 12:10:31 -0400
  Amin Abdulghani <amin@quantiva.com> wrote:
>Hi,
>
>Running Postgres 7.2.1 with python/psycopg (python
>interface for postgres using libpq)/webware application
>server on Solaris, I get a postgres error "could not
>receive data from server Error 0 " when I try to retrieve
>a large text column (16 K) from a table. The query I use
>is "select col from table". However, if I avoid the
>webware application server, this seems to work ok. I am
>just wondering what effect webware could have on the
>postgres client libraries. The postgres server is on a
>different machine. It doesnt seem to be a memory related
>issue as web-ware uses only 5-6 MB on a machine having
>256 MB.
>
>Thanks..
>Amin
>
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>broadcast)---------------------------
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>
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Re: Could not receive data from server

From
Bruce Momjian
Date:
7.4 has a --enable-thread-safety which compiles libpq and ecpg for
threading, with that flag on operating systems that need it.

---------------------------------------------------------------------------

Amin Abdulghani wrote:
> Compiling postgres client with -D_REENTRANT seems to
> remove
> this problem. It seems to have been a thread issue with
> webware (and more specfically errno associated the
> pqReadData).
> On a side note, I noticed that the configure.in for 7.2.1
> doesnt seem to have any option for compiling with the
> above flag. Is it available for the next releases 7.3/7.4?
>
> Thanks..
> Amin
> On Tue, 05 Aug 2003 12:10:31 -0400
>   Amin Abdulghani <amin@quantiva.com> wrote:
> >Hi,
> >
> >Running Postgres 7.2.1 with python/psycopg (python
> >interface for postgres using libpq)/webware application
> >server on Solaris, I get a postgres error "could not
> >receive data from server Error 0 " when I try to retrieve
> >a large text column (16 K) from a table. The query I use
> >is "select col from table". However, if I avoid the
> >webware application server, this seems to work ok. I am
> >just wondering what effect webware could have on the
> >postgres client libraries. The postgres server is on a
> >different machine. It doesnt seem to be a memory related
> >issue as web-ware uses only 5-6 MB on a machine having
> >256 MB.
> >
> >Thanks..
> >Amin
> >
> >---------------------------(end of
> >broadcast)---------------------------
> >TIP 6: Have you searched our list archives?
> >
> >               http://archives.postgresql.org
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 4: Don't 'kill -9' the postmaster
>

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