>From HBase server perspective we need restrict memstore size + block cache size to be max 80%. And memstore size alone can go down to 5% if am not wrong.
We need to be careful when using G1 and giving this 80%. The cache will be mostly full as u said it will be read workload. Making ur working size large. The default value for Initial Heap Occupancy Percentage (IHOP) in G1 is 45%. You can up this. But having this >80% am not sure whether really advisable. -Anoop- On Fri, Mar 17, 2017 at 11:50 PM, jeff saremi <jeffsar...@hotmail.com> wrote: > I'll go through these recommendations, Kevin. Thanks a lot > > ________________________________ > From: Kevin O'Dell <ke...@rocana.com> > Sent: Friday, March 17, 2017 10:55:49 AM > To: user@hbase.apache.org > Subject: Re: Optimizations for a Read-only database > > Hi Jeff, > > You can definitely lower the memstore, the last time I looked there it > had to be set to .1 at lowest it could go. I would not recommend disabling > compactions ever, bad things will occur and it can end up impacting your > read performance greatly. I would recommend looking at the Intel G1GC > <https://software.intel.com/en-us/blogs/2014/06/18/part-1-tuning-java-garbage-collection-for-hbase> > blog series to leverage really large chunks of block cache, and then using > the remaining memory for off heap caching. You should make sure to turn on > things like Snappy compression, FAST_DIFF for data block encoding, and with > all the extra memory you will have available it might be worth using the > ROW+COL bloom filters, though you should have very few underlying HFiles > depending on how often you bulk load. I think short-circuit reads are on by > default these days, but it will greatly speed up read performance if not > already turned on. From an upfront design make sure you pre-split your > tables so your first few bulk loads don't cause split and compaction > pains. Hope this helps! > > On Fri, Mar 17, 2017 at 1:32 PM, jeff saremi <jeffsar...@hotmail.com> wrote: > >> We're creating a readonly database and would like to know the recommended >> optimizations we could do. We'd be loading data via direct write to HFiles. >> >> One thing i could immediately think of is to eliminate the memory for >> Memstore. What is the minimum that we could get away with? >> >> How about disabling some regular operations to save CPU time. I think >> Compaction is one of those we'd like to stop. >> >> thanks >> >> Jeff >> > > > > -- > Kevin O'Dell > Field Engineer > 850-496-1298 | ke...@rocana.com > @kevinrodell > <http://www.rocana.com>
