I understand the point about cache replication but ,if we work with <br>1 or 2 huge memcache servers , if they fail , evrything is dead <br><br>i mean the db it self cannot provide the power needed without the cache so it will
<br>quickly die , untill the cache is restored , and the cache need the mysql to refill .<br><br>How do you manage this in big setups ? <br>do you have a dozen of memcaches around ??? <br><br>the fs has another greate advantage , it cache only used files in fs buffer , so this mean that the ram usage is very small compared to memcache filled with all data .
<br><br>Ps : with reiser fs number of files is not a limitation <br>Ps2 : i think it can be cool to make memcache , cache on disk the unused keys this and this will make it persistent on reboot too.<br><br><br><div><span class="gmail_quote">
2006/6/6, Brian Moon <<a href="mailto:brianm@dealnews.com">brianm@dealnews.com</a>>:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Constantin B wrote:<br>> The purpose of this email is to ask what are the future limitations of<br>> my setup ? I mean for the moment it do the<br>> job , but where is the gotcha ?<br><br>We are slowly migrating from a disk based cache to memcache. We were
<br>already using NFS for our cache storage, so multiple copies was not a<br>problem. We saw issues with multiple apache processes trying to write<br>the same file at the same time. We would sometimes end up with a half
<br>written chunk in the file making the cache obsolete.<br><br>Basically, offloading that work into memory and spread across lots of<br>machines made our caches much more reliable. Faster? I dunno. It<br>depends on the exact parameters. The FS can be very fast.
<br><br>Oh, another issue was what to do with a cache directory with 500,000<br>files in it. Even if its well structured, it can be a nightmare to manage.<br><br>--<br><br>Brian Moon<br>-------------<br><a href="http://dealnews.com/">
http://dealnews.com/</a><br>Its good to be cheap =)<br></blockquote></div><br>