Re: Wierd memory problem with Apache / PHP. Related to - Mailing list pgsql-general

It sounds like a php issue to me more than anythong else. Perhaps PHP's
garbage collection doesn't free the space fast enough?

However, I was looking at the PG source a little to see if it looked
like it was copying the query, and it appears that pqPutMsgBytes (in
fe-misc.c) copies the entire query to a buffer. That could account for
doubling of the query that you send there (since php still holds the
$data string), but still doesn't explain 16MB. Perhaps a little of both
PHP and postgres?

Developers: am I mistaken about libpq copying the entire query before
sending it to the backend? Is there a reason that libpq wouldn't just
send it along to the backend? After all, it seems strange that postgres
would allow a huge query length, yet expect to be able to copy the
entire thing.

Regards,
    Jeff Davis



On Wed, 2005-02-02 at 08:58 +0300, Michael Ben-Nes wrote:
> Hi all,
>
> I got a problem with uploading files which encounter the memory limit
> when their size is not even close to the memory limit itself, let me
> explain.
>
> Here is my code that i made for testing the problem (along the code i
> echoed the function memory_get_usage() to know how much memory was
> allocated already for the script):
>
> $imagefile    =    $_FILES['imagefile']; // recieve the file
> echo memory_get_usage().'<br />';    // 118592 memory bytes allocated
>
> $data = pg_escape_bytea(`cat $imagefile[tmp_name]`);
> echo memory_get_usage().'<br />';    // 5570280 memory bytes allocated
>
> $data = "INSERT INTO test_files (bin_data, filename, filesize, filetype)
>     VALUES ('$data', '$imagefile[name]', '$imagefile[size]',
> '$imagefile[type]')";   // creating the sql for the insert, i called the
> received value also $data cause i dont want to keep the previous $data
> (after all we want to our precious memory no? :))
> echo memory_get_usage().'<br />';    // 5570400 memory bytes allocated
> {changed from b4 only alittle}
>
> if ( !$res = pg_query ($this->conn, $data) )  // try to insert the sql
> string
>     return 'error';
> else
>     return 'gr8';
> echo memory_get_usage().'<br />';    // 5570648 memory bytes allocated
> {again changed only alittle}
>
>
> Now as far as i see the script needed about 5.5MB of memory to upload a
> file of 4.7MB but thats what so weird here... i receive the memory limit
> error even if the php.ini "memory_limit" is set to 16MB! {twice of the
> default of 8MB!}  at 32MB it works fine... but thats way too much..
> I suspect that the problem is connected to the pg_query function itself
> but i didnt find what made it exactly...
>
> Any ideas, knowledge or even just solutions ;) will be extremly helpful.
>
> Thanks in advance,
> Ben-Nes Yonatan
>
>
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