Out Of Memory Error

Sorry to hear about the trouble — the amount of memory needed depends on the content and plugins on the site. On some small sites, 64 or 128MB is enough to complete a scan.

You can try increasing the option “How much memory should Wordfence request when scanning” on the Wordfence Options tab — if you set it to 300 and your host allows it, that amount should only be used during scans, and not regular visits.

Another option is disabling some other plugins, especially if you have any you don’t use anymore. Some plugins use up a lot of memory for each visit, so sometimes disabling one could make a huge difference.

More details are available on these two pages:
Wordfence System Requirements

PHP Fatal Error: Allowed Memory Size…

If this doesn’t help, can you post the whole error? Some hosts limit memory in different ways, and you could be reaching a lower limit than the 256MB you should have available.

-Matt R

Hi Matt, thanks for your help.

I tried increasing it to 300 MB as you suggested and that got rid of the error for one scan, but unfortunately, now it hangs (never ending scan) at:

[Oct 14 07:26:42] Analyzed 2500 files containing 49.49 MB of data so far

I killed the scan, and then restarted it, and got the following error this time at the same place:

[Oct 14 07:33:10] Fatal error: Out of memory (allocated 310902784) (tried to allocate 8192 bytes) in /home/new32344/public_html/wp-content/plugins/wordfence/lib/wordfenceHash.php on line 366

It looks to me like just too many plug-ins – 32??? Unfortunately, a big part of the scan is looking for known problems with the plug-ins, so if I disable them, it kind of defeats the purpose.

It also looks like it is scanning deactivated plug-ins? Is that correct?

I’ve now tried everything – deleting not active plug-ins, not scanning themes, etc., and always getting the memory error. I know the maximum memory with siteground for my hosting plan is 256 MB. It looks like I’m just out of luck?

Ok, since you were able to increase the memory, you can try increasing it more too. 350 MB may work, though that is still a lot for a scan to need.

At the end of a Wordfence scan, when it does finish successfully, it will tell you the peak memory used — if you’re able to test disabling various plugins and see which one decreases that amount significantly, that could be the one that is using a lot of memory.

32 is quite a few plugins, but it’s possible that only one or two of them really use a lot of memory. If you do find which one is using a lot of memory, and can find a similar plugin that serves the same purpose, that could help, and would likely make the site perform faster, too. (Of course, if you really like the plugins you’re using, you might not want to replace any.)

It is normal for deactivated plugins to still be scanned, too. Hackers can hide code in any php file, so it is still necessary to scan them. When a plugin is disabled, WordPress doesn’t load it into memory, so that leaves more memory for Wordfence to use, even though the files are still scanned.

-Matt R

I replied before seeing your last post, while I was writing my last one — if you’re able to temporarily disable all other plugins, and switch to a default theme like “twentyfifteen”, then try a scan, you can see the minimum memory that Wordfence and WordPress use for a scan, mentioned above — if that is still high, let me know what number you see.

If it does get much lower, then you could try enabling some plugins, and see which one increases it. Of course, this would take a very long time, if going one-by-one, so you might do them in groups. If enabling a few plugins causes a huge jump in memory usage or a scan failure, then you’ll know one of the plugins in that group was using a lot of memory.

You won’t have to delete the plugins to test this — you can still leave them in place.

If it still doesn’t work, I can explain debugging mode, which we can use to get more detail from a scan, which may help too.

-Matt R