Is it possible you’re hitting a PHP memory limit? Not sure what the debug output is from, is that from PHP error log? I’d expect to see some kind of error if things hang up enough to need to be restarted..

Here you are the “real” error.log

As you said it seems to be a memory error: http://pastebin.com/raw.php?i=2vWSn8QA

Could you help me to find a solution?

Quite simply the more you have running (i.e plugins) the more PHP memory you will need.

So yes, increase it! You should be able to manually increase it in the php.ini file, although I can’t tell you where that file will be exactly as it could differ depending on installation.

You might be able to edit it directly in your hosting panel (cPanel maybe?). I know locally mine is in Wamp > bin > php > phpversion > php.ini..

Look for the line:

; Maximum amount of memory a script may consume (128MB)
; http://php.net/memory-limit
memory_limit = 128M

Although mine is 128M, yours might be different. Change it to suit your needs.

If you can’t access it you might need to ask your host.

I’ve upgraded memory limit to 528M ( it was 128M) just to be sure…but the error is the the same( memory allocation ) followed by a segmentation fault

extra 400 MB for sp buddypress plugin should be enough…

Did you restart the server after making the change?

If so, it’s entirely possible your host doesn’t allow PHP memory changes or it might have a ceiling so to speak – I’m no expert on that subject, you might need to ask them.

I’m on a vps with full access to OS

I’ve restarted apache after changes. Isn’t it enough? i’ll do a try

After restart the memory error seems  has been gone

but the segmentation fault persists and both admin panel and front end are blank ( simply it dies )

Segmentation error? What are you seeing?

[Thu Nov 05 18:58:27.902882 2015] [core:notice] [pid 3494] AH00051: child pid 4287 exit signal Segmentation fault (11), possible coredump in /etc/apache2
[Thu Nov 05 18:58:35.911464 2015] [core:notice] [pid 3494] AH00051: child pid 4276 exit signal Segmentation fault (11), possible coredump in /etc/apache2

There was an issue – well over a year ago – that would cause a memory error when the notifications module of buddypress was disabled. This was, of course, fixed.

On that particular occasion, @mr-papa – who works our BP plugin, suggested that the user…

uninstall our buddypress plugin… deactivate the wp buddypress plugin… activate our buddypress plugin.. then activate the wp buddypress plugin…

And the user came back and said that this resolved it. Trouble is, I have no idea why he made that suggestion! Might be worth a quick try…

I’ve followed your instructions but nothing changed 🙁

It’s really strange that only this plugin generates such problem

Apologies for the delay. I was hoping to bring in @mr-papa on this question but his flight home was severely delayed last night – which he spent a lot of at an airport! So he didn’t get any forum time last night as expected. I will talk to him today.

Thanks @yellow-swordfish 

I need this plugin since i’m using buddypress notification

odd… havent seen one of these in quite some time – all were solved after an update due to buddypress code change…  assume you are using latest version of buddypress?  do you have any buddypress add on plugins?

did to see what you are doing for avatars and make sure you dont have an infinite loop… on forum – profile – avatars, what options do you have for avatar priorities and for wp avatar replacement?  Then on forum – components – buddypress, are you using just bp avatars or just sp avatars?