Restrict search when the server load is high

From experience searches on large forums can slow the server down a lot.

Here's a dead simple hack that lets you disable searches when the load average reaches a defined level. Moderators are exempt from the search ban.

There's are just two changes to be made:

in search.php find:

PHP Code:

if (!$vboptions['enablesearches'])
{
        eval(print_standard_error('error_searchdisabled'));
} 


add below it:

PHP Code:

// automatically block search requests when the server is busy
$search_load_trigger=5;
if ( (!($permissions['adminpermissions'] & ISMODERATOR)) AND PHP_OS == 'Linux' AND @file_exists('/proc/loadavg') AND $filestuff = @file_get_contents('/proc/loadavg'))
{
        $loadavg = explode(' ', $filestuff);
        if (trim($loadavg[0]) > $search_load_trigger)
        {
                eval(print_standard_error('error_searchdisabled'));
        }
} 


The trigger level is based on the current (1 minute) load average. It can be changed by editing the $search_load_trigger variable.

You may also wish to change the searchdisabled phrase to something like:

Searching has been disabled. This is most likely automatic and due to high server load. Please try again later.

[babolo]

nice hack maybe i'll install it

[yoyoyoyo]

hmm.. interesting. thanks for sharing. I may install this later, though my site is on a shared server and loads can get pretty dang high

[UK Jimbo]

Be really interested to get everyone's feedback on how well this has worked for you.

[Jen]

I just installed it.. and the search feature stopped working alltogether. All I get now is a blank page.

Did some debugging and it's harfing somewhere after the first IF, won't even display a print after the if statement and nothing inside it.

Here's where it seems to die on me: @file_get_contents('/proc/loadavg').

[UK Jimbo]

Originally Posted by Jen

I just installed it.. and the search feature stopped working alltogether. All I get now is a blank page.

Did some debugging and it's harfing somewhere after the first IF, won't even display a print after the if statement and nothing inside it.

Here's where it seems to die on me: @file_get_contents('/proc/loadavg').

I should have pointed out that this will only work on Linux machines or *NIX flavours that support the proc file system and specificially /proc/loadavg

It'd be great if you could drop me a PM with some further error message/debug Jen. It definitely shouldn't present you with a blank page.

[Jen]

PM Inbound UK. I'm running Redhat and /proc/loadavg exists, I'm wondering if it can get the file contents though.

[Polo]

Interesting...

[hollyboy]

where do I set the average server load number?

[UK Jimbo]

Originally Posted by hollyboy

where do I set the average server load number?

$search_load_trigger=5;

at the top.

Where 5 is a one minute load average of 5.