> Hi, > Does anybody know good way to handle OOM during set operation? Server is > fully calcified :) (no new pages to allocate) and i have this issue for > slab 17 > STAT items:17:number 16128 > STAT items:17:age 90 > STAT items:17:evicted 246790897 > STAT items:17:evicted_nonzero 246790874 > STAT items:17:evicted_time 90 > STAT items:17:outofmemory 33098 > STAT items:17:tailrepairs 0 > STAT items:17:reclaimed 1183 > STAT items:17:expired_unfetched 196 > STAT items:17:evicted_unfetched 143699820 > > running memcached : STAT version 1.4.15
"stats slabs" ? Is memory unbalanced from other slabs? > nothing except reboot periodically comes to my mind but this solution does > not make me happy :) There's the slab rebalance feature. OOM errors only happen when there is truly very few pages free and all of the ones in the tail are locked, or there's a bug. It should always evict. The rebalance feature is documented in doc/protocol.txt. However your eviction seems to be very highly pressured. The evicted_unfetched stat is high compared to the tota number of evictions. So they're not even staying in long enough to get fetched again. There aren't that many OOM errors overall, so perhaps you are just hitting that slab way too hard and occasionally locking everything in the tail. You either need to add more memory to the total system or rebalance them. > other option - enable compression to allow more items but need to experiment > (why memcached does not provide server side compression? as i see in > stats memcached cpu is not used, so would be good to utilize it.) Very high rate of access is expected and the ratio of clients to servers might be high, so compression is done in the client instead. It was also designed to let you run it wherever there's free memory (extra installed in webservers/etc) so it wants to avoid excess cpu usage. It's a trivial switch either way. Also consider upgrading to .17 or .19. might be some good fixes. -- --- 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 [email protected]. For more options, visit https://groups.google.com/d/optout.
