We did this query, most our files are less than 100MB. Our heap setting are like (they are calculatwed using scipr in cassandra.env): MAX_HEAP_SIZE="8GB" HEAP_NEWSIZE="2GB" which is maximum recommended by DataStax.
What values do you think we should try? On Thu, Feb 26, 2015 at 10:06 AM, Roland Etzenhammer < r.etzenham...@t-online.de> wrote: > Hi Piotrek, > > your disks are mostly idle as far as I can see (the one with 17% busy > isn't that high on load). One thing came up to my mind did you look on > the sizes of your sstables? I did this with something like > > find /var/lib/cassandra/data -type f -size -1k -name "*Data.db" | wc > find /var/lib/cassandra/data -type f -size -10k -name "*Data.db" | wc > find /var/lib/cassandra/data -type f -size -100k -name "*Data.db" | wc > ... > find /var/lib/cassandra/data -type f -size -1000000k -name "*Data.db" | wc > > Your count is growing from opscenter - and if there are many really > small tables I would guess you are running out of heap. If memory > pressure is high it is likely that there will be much flushes of > memtables to disk with many small files - had this once. You can > increase heap in cassandra-env.sh, but be careful. > > Best regards, > Roland > >
