#4046 (ok 4.0.6) Exporting huge Tables causes memory-Problems

[H. Teichmann]

We got a Problem with the 4.0.4.1 Version and exporting of huge Tables oder Databases. Since we upgraded to Major-Release 4 exporting of huge Tables wont work and causes errors like

Out of memory (allocated 1270349824) (tried to allocate 629166081 bytes) in libraries/Response.class.php

or

Allowed memory size of 1073741824 bytes exhausted (tried to allocate 697377364 bytes) in libraries/OutputBuffering.class.php on line 114

A raw-Dump of this Table is about 578MB (very close to that 62916.. bytes), and we already tried to set memory_limit to maximum-value but it didnt help.

I suspect Output-Buffering to be a Problem, the Content of the Output-Buffer is copied on some Parts, for example in OutputBuffering.class.php

        $buffer->_content = ob_get_contents();
        ob_end_clean();

At the moment when ob_get_contents is called the buffer-content is hold twice times and causing memory Problems.

According to my Customer, exporting this huge Table was no Problem in phpMyAdmin 3.

Thanks for help!

[Michal Čihař]

I think output buffering should not be used at all for export - it has own logic for sending data to client to reduce memory usage.

[brian m. carlson]

We're also seeing this problem. Usually a database of at least 50 MB is sufficient to trigger this, but sometimes it takes a larger database.

[Stacey Fuller]

I am also having this problem. One of my clients has a table with a large amount of data in it (>4000) entries. I was able to back up this database previously in version 3 releases and now it times out using version 4.

[jimmy silva]

Same issue here can not export any databases larger then 52 MB

[Mat Connolley]

We're also having this problem - in v3 we could export 100 small databases in one go, now we have to export them all separately :(

[J. Nick Koston]

Is there a resolution ETA on this issue?

[Mat Connolley]

Hi,

I'm currently out of the office, returning on 30th August. If you need assistance please call me on 07590 676544.

Best wishes,

Mat.

[Marc Delisle]

I confirm the problem and it's going to be our priority, targetting a fix for 4.0.6-rc2.

[J. Nick Koston]

Thank you. Please email me where to send beer (or other preferences)

[Mat Connolley]

Hi,

I'm currently out of the office, returning on 30th August. If you need assistance please call me on 07590 676544.

Best wishes,

Mat.

[Marc Delisle]

Here is a fix I propose for the upcoming 4.0.6-rc2, please confirm:
https://github.com/phpmyadmin/phpmyadmin/commit/5298602f8edb4475fce5d299532c7780e0e314a5.patch

[Mat Connolley]

Thanks Marc! I can confirm that it's working again for us for an export of 410MB.