I've been having problems with memcached since I set it up and I think its probably because I don't 100% understand it. <br>
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We have 20 php servers, all of with the same specs, each one with 4GB of RAM and 1GB of that is for memcached.<br>
<br>
Each has the same php scripts. Every single script starts with this:<br>
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memcache_pconnect which connects to the same IP, which is our first PHP
server. This is the same seever which is connected to by every server.
Then we have memcache_add_server for all of the other 19 php servers we
have. <br>
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So for example:<br>
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$this->memcache_id = memcache_pconnect('<a href="http://1.1.1.1">1.1.1.1</a>', 11211); <br>
<br>
memcache_add_server($this->memcache_id, '<a href="http://1.1.1.2">1.1.1.2</a>', 11212,
false); <br>
<br>
memcache_add_server($this->memcache_id, '<a href="http://1.1.1.3">1.1.1.3</a>', 11211, false);<br>
<br>
With that set up on all of the servers, memcached works like it should
most of the time. But theres the ocasional problems where data we
deleted from the cache still appears, even hours after it was deleted.<br>
<br>
If we set it to persinstant connections, the whole thing stops working.
They don't fail, the processes stay alive, but memcached stops adding
to getting the keys.<br>
<br>
And if we make any edits to the connection information, the whole thing
acts crazy and I usually have to kill every process on every server,
restart apache on every server, start every memcached process again and
then add the memcached connect info at the top of the scripts again.<br>
<br>
What I don't understand is, how does the API know which server to find the key on? <br>
<br>
And why does it act so strange when persistant connections are enabled? Is it because theres 30 servers?<br>
<br>
Thanks for your help<br>
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