If you're using SizeTieredCompactionStrategy the disk space may double temporarily during compaction. That's one of the big drawback of SizedTiered. Since you're on SSD, why not test switching to LeveledCompaction ? Put a node on write survey mode to see if this change has any impact on your I/O, CPU and node stability.
On Thu, Jul 24, 2014 at 11:56 PM, Kevin Burton <bur...@spinn3r.com> wrote: > I just bootstrapped a new node. > > The box had about 220GB of data on it on a 400GB SSD drive. > > I triggered a full compaction after it bootstrapped, and it ran out of > disk space about 15 minutes later. so now that node is dead :-( > > I would have assumed that vnodes meant that I could keep my drive near > 100% full… > > so during a major compaction it would just compact the first vnode, then > move on to the second. > > this would be analogous to bigtable / hbase regions. > > but … that doesn't seem to be the case. (so bad assumption on my part) > Both in terms of me actually seeing the disk fill up, and also the case of > my disk not having separate SSTables for each vnode. > > So now I have these SSDs that I have to keep at > 50% capacity at all > times. > > I can see why on HDDs having too many files would be an issue. > > But on SSDs this is less of a problem. > > Perhaps some hybrid where vnodes are chunked together in one contiguous > region? > > Is there a way to fix this problem? I would like to get more usage out of > my SSDs... > > -- > > Founder/CEO Spinn3r.com > Location: *San Francisco, CA* > blog: http://burtonator.wordpress.com > … or check out my Google+ profile > <https://plus.google.com/102718274791889610666/posts> > <http://spinn3r.com> > >
