i think repcached is used with DRBD solutions two servers, if one server get down the other 'hot server' take the 'cluster' ip address and start services without recreating the cache, with a low startup time between fail and hot server start
2014-08-05 12:45 GMT-03:00 PenguinWhispererThe < th3penguinwhispe...@gmail.com>: > Hi all, > > I wonder what the added value for repcached is( > http://repcached.lab.klab.org/). > It replicates the objects to both configured nodes. So you can read the > cached value on all nodes even if it was added through the memcached on the > other node. > > In the normal memcached there is a constant hash algorithm so you will hit > the correct server when reading a previously set value. > When this server goes down I assume you just "cache-miss" and get your > data directly from the database and then cache it on another memcached node? > > I would assume repcache would give some kind of HA however I don't see how > this can't be accomplished by the normal memcached. > Ok, you loose cache but it will be cached on another node again. In that > way it actually seems like repcached adds overhead. > > Another thought I had is that if one very frequently executed query gets a > hash that is on for example memcache server X that all subsequent clients > that need the same data will also be sent to server X. So more load will go > to that server. > Am I thinking right here? Is that the purpose of repcached? Maybe a > workaround could be to just create a few hashes with the same data so you > can be sure that those will approximately be balanced over the different > memcached servers? > > Note that I never used memcached/repcached but I'm trying to understand if > we actually need this in our organisation. There seems to be an issue with > a segmentation fault and I want to make sure I don't spend a lot of time > while there might be a better solution. Repcached isn't maintained anymore > either. So maybe it's better to look at a long term solution. > > Thanks in advance! > > -- > > --- > You received this message because you are subscribed to the Google Groups > "memcached" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to memcached+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/d/optout. > -- Roberto Spadim -- --- You received this message because you are subscribed to the Google Groups "memcached" group. To unsubscribe from this group and stop receiving emails from it, send an email to memcached+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
