hi, all I retest the YCSB load data, and here is a situation which may explain the load data blocked.
I use too many threads to insert values, so the flush thread is not effectively to handle all memstore, and the user9099 memstore is queued at last, and waiting for flush too long which blocks the YCSB request. Then I modify the configuration, set hbase.hstore.flusher.count to 20 (default value is 2), and run the YCSB to load data with 32 threads, it can run for 1 hour (with 2 threads just run for less than half 1 hour). On Nov 20, 2014, at 23:20, louis.hust <[email protected]> wrote: > Hi Ram, > > Thanks for your reply! > > I use YCSB workloadc to load data, and from the web request monitor i can see > that > the write requests are distributed among all regions, so i think the data get > distributed, > > And there are 32 thread writing to the region server, may be the concurrency > and write rate is too high. > The writes are blocked but the memstore do not get flushed, i want to know > why? > > The jvm heap is 64G and hbase.regionserver.global.memstore.size is > default(0.4) about 25.6G, > and hbase.hregion.memstore.flush.size is default(132M), but the blocked > memstore user9099 > reach 512m and do not flush at all. > > other memstore related options: > > hbase.hregion.memstore.mslab.enabled=true > hbase.regionserver.global.memstore.upperLimit=0.4 > hbase.regionserver.global.memstore.lowerLimit=0.38 > hbase.hregion.memstore.block.multiplier=4 > > > On Nov 20, 2014, at 20:38, ramkrishna vasudevan > <[email protected]> wrote: > >> Check if the writes are going to that particular region and its rate is too >> high. Ensure that the data gets distributed among all regions. >> What is the memstore size? >> >> If the rate of writes is very high then the flushing will get queued and >> until the memstore gets flushed such that it goes down the global upper >> limit writes will be blocked. >> >> I don't have the code now to see the exact config related to memstore. >> >> Regards >> Ram >> >> On Thu, Nov 20, 2014 at 4:50 PM, louis.hust <[email protected]> wrote: >> hi all, >> >> I build an HBASE test environment, with three PC server, with CHD 5.1.0 >> >> pc1 pc2 pc3 >> >> pc1 and pc2 as HMASTER and hadoop namenode >> pc3 as RegionServer and datanode >> >> Then I create user as following: >> create 'usertable', 'family', {SPLITS => (1..100).map {|i| >> "user#{1000+i*(9999-1000)/100}"} } >> Using YCSB for load data as following: >> >> ./bin/ycsb load hbase -P workloads/workloadc -p columnfamily=family -p >> recordcount=1000000000 -p threadcount=32 -s > result/workloadc >> >> >> But when after a while, the ycsb return with following error: >> >> 14/11/20 12:23:44 INFO client.AsyncProcess: #15, table=usertable, >> attempt=35/35 failed 715 ops, last exception: >> org.apache.hadoop.hbase.RegionTooBusyException: >> org.apache.hadoop.hbase.RegionTooBusyException: Above memstore limit, >> regionName=usertable,user9099,1416453519676.2552d36eb407a8af12d2b58c973d68a9., >> server=l-hbase10.dba.cn1,60020,1416451280772, memstoreSize=536897120, >> blockingMemStoreSize=536870912 >> at >> org.apache.hadoop.hbase.regionserver.HRegion.checkResources(HRegion.java:2822) >> at >> org.apache.hadoop.hbase.regionserver.HRegion.batchMutate(HRegion.java:2234) >> at >> org.apache.hadoop.hbase.regionserver.HRegion.batchMutate(HRegion.java:2201) >> at >> org.apache.hadoop.hbase.regionserver.HRegion.batchMutate(HRegion.java:2205) >> at >> org.apache.hadoop.hbase.regionserver.HRegionServer.doBatchOp(HRegionServer.java:4253) >> at >> org.apache.hadoop.hbase.regionserver.HRegionServer.doNonAtomicRegionMutation(HRegionServer.java:3469) >> at >> org.apache.hadoop.hbase.regionserver.HRegionServer.multi(HRegionServer.java:3359) >> at >> org.apache.hadoop.hbase.protobuf.generated.ClientProtos$ClientService$2.callBlockingMethod(ClientProtos.java:29503) >> at org.apache.hadoop.hbase.ipc.RpcServer.call(RpcServer.java:2012) >> at org.apache.hadoop.hbase.ipc.CallRunner.run(CallRunner.java:98) >> at >> org.apache.hadoop.hbase.ipc.SimpleRpcScheduler.consumerLoop(SimpleRpcScheduler.java:160) >> at >> org.apache.hadoop.hbase.ipc.SimpleRpcScheduler.access$000(SimpleRpcScheduler.java:38) >> at >> org.apache.hadoop.hbase.ipc.SimpleRpcScheduler$1.run(SimpleRpcScheduler.java:110) >> at java.lang.Thread.run(Thread.java:744) >> on l-hbase10.dba.cn1,60020,1416451280772, tracking started Thu Nov 20 >> 12:15:07 CST 2014, retrying after 20051 ms, replay 715 ops. >> >> >> It seems the user9099 region is too busy, so I lookup the memstore metrics >> in web: >> >> >> As you see, the user9099 is bigger than other region, I think it is >> flushing, but after a while, it does not change to a small size and YCSB >> quit finally. >> >> But when i change the concurrency threads to 4, all is right. I want to know >> why? >> >> Any idea will be appreciated. >> >> >> >
