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From: Bryan Beaudreault <bbeaudreault@hubspot.com>
Date: Mon, 30 Nov 2015 20:54:19 +0000
Message-ID: 
 <CANZDn9v_U_CjfGUNunOAmmup_V3oJNj-kkBDWMFMS2BGSqfZsA@mail.gmail.com>
Subject: Re: Performance degradation between CDH5.3.1(HBase0.98.6) and
 CDH5.4.5(HBase1.0.0)
To: HBase Dev List <dev@hbase.apache.org>
Cc: "user@hbase.apache.org" <user@hbase.apache.org>
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Should this be added as a known issue in the CDH or hbase documentation? It
was a severe performance hit for us, all of our regionservers were sitting
at a few thousand queued requests.

On Mon, Nov 30, 2015 at 3:53 PM Bryan Beaudreault <bbeaudreault@hubspot.com=
>
wrote:

> Yea, they are all over the place and called from client and coprocessor
> code. We ended up having no other option but to rollback, and aside from =
a
> few NoSuchMethodErrors due to API changes (Put#add vs Put#addColumn), it
> seems to be working and fixing our problem.
>
> On Mon, Nov 30, 2015 at 3:47 PM Stack <stack@duboce.net> wrote:
>
>> Rollback is untested. No fix in 5.5. I was going to work on this now.
>> Where
>> are your counters Bryan? In their own column family or scattered about i=
n
>> a
>> row with other Cell types?
>> St.Ack
>>
>> On Mon, Nov 30, 2015 at 10:28 AM, Bryan Beaudreault <
>> bbeaudreault@hubspot.com> wrote:
>>
>> > Is there any update to this? We just upgraded all of our production
>> > clusters from CDH4 to CDH5.4.7 and, not seeing this JIRA listed in the
>> > known issues, did not not about this.  Now we are seeing perfomance
>> issues
>> > across all clusters, as we make heavy use of increments.
>> >
>> > Can we roll forward to CDH5.5 to fix? Or is our only hope to roll back
>> to
>> > CDH 5.3.1 (if that is possible)?
>> >
>> >
>> > On Thu, Sep 24, 2015 at 5:06 AM =E9=88=B4=E6=9C=A8=E4=BF=8A=E8=A3=95 <=
brfrn169@gmail.com> wrote:
>> >
>> > > Thank you St.Ack!
>> > >
>> > > I would like to follow the ticket.
>> > >
>> > > Toshihiro Suzuki
>> > >
>> > > 2015-09-22 14:14 GMT+09:00 Stack <stack@duboce.net>:
>> > >
>> > > > Back to this problem. Simple tests confirm that as is, the
>> > > > single-queue-backed MVCC instance can slow Region ops if some othe=
r
>> row
>> > > is
>> > > > slow to complete. In particular Increment, checkAndPut, and batch
>> > > mutations
>> > > > are effected. I opened HBASE-14460 to start in on a fix up. Lets
>> see if
>> > > we
>> > > > can somehow scope mvcc to row or at least shard mvcc so not all
>> Region
>> > > ops
>> > > > are paused.
>> > > >
>> > > > St.Ack
>> > > >
>> > > >
>> > > > On Mon, Sep 14, 2015 at 4:15 AM, =E9=88=B4=E6=9C=A8=E4=BF=8A=E8=A3=
=95 <brfrn169@gmail.com> wrote:
>> > > >
>> > > > > > Thank you for the below reasoning (with accompanying helpful
>> > > diagram).
>> > > > > > Makes sense. Let me hack up a test case to help with the
>> > > illustration.
>> > > > It
>> > > > > > is as though the mvcc should be scoped to a row only... Writes
>> > > against
>> > > > > > other rows should not hold up my read of my row. Tag an mvcc
>> with a
>> > > > 'row'
>> > > > > > scope so we can see which on-going writes pertain to current
>> > > operation?
>> > > > > Thank you St.Ack! I think this approach would work.
>> > > > >
>> > > > > > You need to read back the increment and have it be 'correct' a=
t
>> > > > increment
>> > > > > > time?
>> > > > > Yes, we need it.
>> > > > >
>> > > > > I would like to help if there is anything I can do.
>> > > > >
>> > > > > Thanks,
>> > > > > Toshihiro Suzuki
>> > > > >
>> > > > >
>> > > > > 2015-09-13 14:11 GMT+09:00 Stack <stack@duboce.net>:
>> > > > >
>> > > > > > Thank you for the below reasoning (with accompanying helpful
>> > > diagram).
>> > > > > > Makes sense. Let me hack up a test case to help with the
>> > > illustration.
>> > > > It
>> > > > > > is as though the mvcc should be scoped to a row only... Writes
>> > > against
>> > > > > > other rows should not hold up my read of my row. Tag an mvcc
>> with a
>> > > > 'row'
>> > > > > > scope so we can see which on-going writes pertain to current
>> > > operation?
>> > > > > >
>> > > > > > You need to read back the increment and have it be 'correct' a=
t
>> > > > increment
>> > > > > > time?
>> > > > > >
>> > > > > > (This is a good one)
>> > > > > >
>> > > > > > Thank you Toshihiro Suzuki
>> > > > > > St.Ack
>> > > > > >
>> > > > > > On Sat, Sep 12, 2015 at 8:09 AM, =E9=88=B4=E6=9C=A8=E4=BF=8A=
=E8=A3=95 <brfrn169@gmail.com>
>> wrote:
>> > > > > >
>> > > > > > > St.Ack,
>> > > > > > >
>> > > > > > > Thank you for your response.
>> > > > > > >
>> > > > > > > Why I make out that "A region lock (not a row lock) seems to
>> > occur
>> > > in
>> > > > > > > waitForPreviousTransactionsComplete()" is as follows:
>> > > > > > >
>> > > > > > > A increment operation has 3 procedures for MVCC.
>> > > > > > >
>> > > > > > > 1. mvcc.waitForPreviousTransactionsComplete();
>> > > > > > >
>> > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> https://github.com/cloudera/hbase/blob/cdh5.4.5-release/hbase-server/src=
/main/java/org/apache/hadoop/hbase/regionserver/HRegion.java#L6712
>> > > > > > >
>> > > > > > > 2. w =3D mvcc.beginMemstoreInsertWithSeqNum(mvccNum);
>> > > > > > >
>> > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> https://github.com/cloudera/hbase/blob/cdh5.4.5-release/hbase-server/src=
/main/java/org/apache/hadoop/hbase/regionserver/HRegion.java#L6721
>> > > > > > >
>> > > > > > > 3. mvcc.completeMemstoreInsertWithSeqNum(w, walKey);
>> > > > > > >
>> > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> https://github.com/cloudera/hbase/blob/cdh5.4.5-release/hbase-server/src=
/main/java/org/apache/hadoop/hbase/regionserver/HRegion.java#L6893
>> > > > > > >
>> > > > > > >
>> > > > > > > I think that MultiVersionConsistencyControl's writeQueue can
>> > cause
>> > > a
>> > > > > > region
>> > > > > > > lock.
>> > > > > > >
>> > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> https://github.com/cloudera/hbase/blob/cdh5.4.5-release/hbase-server/src=
/main/java/org/apache/hadoop/hbase/regionserver/MultiVersionConsistencyCont=
rol.java#L42-L43
>> > > > > > >
>> > > > > > >
>> > > > > > > Step 2 adds to a WriteEntry to writeQueue.
>> > > > > > >
>> > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> https://github.com/cloudera/hbase/blob/cdh5.4.5-release/hbase-server/src=
/main/java/org/apache/hadoop/hbase/regionserver/MultiVersionConsistencyCont=
rol.java#L102-L108
>> > > > > > >
>> > > > > > > Step 3 removes the WriteEntry from writeQueue.
>> > > > > > >
>> > > > > > > completeMemstoreInsertWithSeqNum(w, walKey) ->
>> > > > > > > waitForPreviousTransactionsComplete(e) -> advanceMemstore(w)
>> > > > > > >
>> > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> https://github.com/cloudera/hbase/blob/cdh5.4.5-release/hbase-server/src=
/main/java/org/apache/hadoop/hbase/regionserver/MultiVersionConsistencyCont=
rol.java#L127
>> > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> https://github.com/cloudera/hbase/blob/cdh5.4.5-release/hbase-server/src=
/main/java/org/apache/hadoop/hbase/regionserver/MultiVersionConsistencyCont=
rol.java#L235
>> > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> https://github.com/cloudera/hbase/blob/cdh5.4.5-release/hbase-server/src=
/main/java/org/apache/hadoop/hbase/regionserver/MultiVersionConsistencyCont=
rol.java#L160
>> > > > > > >
>> > > > > > > Step 1 adds a WriteEntry w in beginMemstoreInsert() to
>> writeQueue
>> > > and
>> > > > > > waits
>> > > > > > > until writeQueue is empty or writeQueue.getFirst() =3D=3D w.
>> > > > > > >
>> > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> https://github.com/cloudera/hbase/blob/cdh5.4.5-release/hbase-server/src=
/main/java/org/apache/hadoop/hbase/regionserver/MultiVersionConsistencyCont=
rol.java#L201-L204
>> > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> https://github.com/cloudera/hbase/blob/cdh5.4.5-release/hbase-server/src=
/main/java/org/apache/hadoop/hbase/regionserver/MultiVersionConsistencyCont=
rol.java#L206-L241
>> > > > > > >
>> > > > > > >
>> > > > > > > I think when a handler thread is processing between step 2 a=
nd
>> > step
>> > > > 3,
>> > > > > > the
>> > > > > > > other handler threads can wait at step 1 until the thread
>> > completes
>> > > > > step
>> > > > > > 3
>> > > > > > > This is depicted as follows:
>> > > > > > >
>> > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> https://gist.githubusercontent.com/brfrn169/cb4f2c157129330cd932/raw/86d=
6aae5667b0fe006b16fed80f1b0c4945c7fd0/region_lock.png
>> > > > > > >
>> > > > > > >
>> > > > > > > Actually, in the thread dump of our region server, many
>> handler
>> > > > threads
>> > > > > > > (RW.default.writeRpcServer.handler) wait at Step 1
>> > > > > > > (waitForPreviousTransactionsComplete()).
>> > > > > > >
>> > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> https://gist.githubusercontent.com/brfrn169/cb4f2c157129330cd932/raw/86d=
6aae5667b0fe006b16fed80f1b0c4945c7fd0/thread_dump.txt
>> > > > > > >
>> > > > > > > Many handler threads wait at this:
>> > > > > > >
>> > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> https://github.com/cloudera/hbase/blob/cdh5.4.5-release/hbase-server/src=
/main/java/org/apache/hadoop/hbase/regionserver/MultiVersionConsistencyCont=
rol.java#L224
>> > > > > > >
>> > > > > > >
>> > > > > > > > Is it possible you are contending on a counter post-upgrad=
e?
>> > Is
>> > > it
>> > > > > > > > possible that all these threads are trying to get to the
>> same
>> > row
>> > > > to
>> > > > > > > update
>> > > > > > > > it? Could the app behavior have changed?  Or are you
>> thinking
>> > > > > increment
>> > > > > > > > itself has slowed significantly?
>> > > > > > > We have just upgraded HBase, not changed the app behavior. W=
e
>> are
>> > > > > > thinking
>> > > > > > > increment itself has slowed significantly.
>> > > > > > > Before upgrading HBase, it was good throughput and latency.
>> > > > > > > Currently, to cope with this problem, we split the regions
>> > finely.
>> > > > > > >
>> > > > > > > Thanks,
>> > > > > > >
>> > > > > > > Toshihiro Suzuki
>> > > > > > >
>> > > > > > >
>> > > > > > > 2015-09-09 15:29 GMT+09:00 Stack <stack@duboce.net>:
>> > > > > > >
>> > > > > > > > On Tue, Sep 8, 2015 at 10:22 PM, =E9=88=B4=E6=9C=A8=E4=BF=
=8A=E8=A3=95 <brfrn169@gmail.com>
>> > > wrote:
>> > > > > > > >
>> > > > > > > > > Ted,
>> > > > > > > > >
>> > > > > > > > > Thank you for your response.
>> > > > > > > > >
>> > > > > > > > > I uploaded the complete stack trace to Gist.
>> > > > > > > > >
>> > > > > > > > > https://gist.github.com/brfrn169/cb4f2c157129330cd932
>> > > > > > > > >
>> > > > > > > > >
>> > > > > > > > > I think that increment operation works as follows:
>> > > > > > > > >
>> > > > > > > > > 1. get row lock
>> > > > > > > > > 2. mvcc.waitForPreviousTransactionsComplete() // wait fo=
r
>> all
>> > > > prior
>> > > > > > > MVCC
>> > > > > > > > > transactions to finish
>> > > > > > > > > 3. mvcc.beginMemstoreInsertWithSeqNum() // start a
>> > transaction
>> > > > > > > > > 4. get previous values
>> > > > > > > > > 5. create KVs
>> > > > > > > > > 6. write to Memstore
>> > > > > > > > > 7. write to WAL
>> > > > > > > > > 8. release row lock
>> > > > > > > > > 9. mvcc.completeMemstoreInsertWithSeqNum() // complete t=
he
>> > > > > > transaction
>> > > > > > > > >
>> > > > > > > > > A instance of MultiVersionConsistencyControl has a pendi=
ng
>> > > queue
>> > > > of
>> > > > > > > > writes
>> > > > > > > > > named writeQueue.
>> > > > > > > > > Step 2 puts a WriteEntry w to writeQueue and waits until
>> > > > writeQueue
>> > > > > > is
>> > > > > > > > > empty or writeQueue.getFirst() =3D=3D w.
>> > > > > > > > > Step 3 puts a WriteEntry to writeQueue and step 9 remove=
s
>> the
>> > > > > > > WriteEntry
>> > > > > > > > > from writeQueue.
>> > > > > > > > >
>> > > > > > > > > I think that when a handler thread is processing between
>> > step 2
>> > > > and
>> > > > > > > step
>> > > > > > > > 9,
>> > > > > > > > > the other handler threads can wait until the thread
>> completes
>> > > > step
>> > > > > 9.
>> > > > > > > > >
>> > > > > > > > >
>> > > > > > > > That is right. We need to read, after all outstanding
>> updates
>> > are
>> > > > > > done...
>> > > > > > > > because we need to read the latest update before we go to
>> > > > > > > modify/increment
>> > > > > > > > it.
>> > > > > > > >
>> > > > > > > > How do you make out this?
>> > > > > > > >
>> > > > > > > > "A region lock (not a row lock) seems to occur in
>> > > > > > > > waitForPreviousTransactionsComplete()."
>> > > > > > > >
>> > > > > > > > In 0.98.x we did this:
>> > > > > > > >
>> > > > > > > > mvcc.completeMemstoreInsert(mvcc.beginMemstoreInsert());
>> > > > > > > >
>> > > > > > > > ... and in 1.0 we do this:
>> > > > > > > >
>> > > > > > > > mvcc.waitForPreviousTransactionsComplete() which is this..=
..
>> > > > > > > >
>> > > > > > > > +  public void waitForPreviousTransactionsComplete() {
>> > > > > > > > +    WriteEntry w =3D beginMemstoreInsert();
>> > > > > > > > +    waitForPreviousTransactionsComplete(w);
>> > > > > > > > +  }
>> > > > > > > >
>> > > > > > > > The mvcc and region sequenceid were merged in 1.0 (
>> > > > > > > > https://issues.apache.org/jira/browse/HBASE-8763). Previou=
s
>> > mvcc
>> > > > and
>> > > > > > > > region
>> > > > > > > > sequenceid would spin independent of each other. Perhaps
>> this
>> > > > > > responsible
>> > > > > > > > for some slow down.
>> > > > > > > >
>> > > > > > > > That said, looking in your thread dump, we seem to be down
>> in
>> > the
>> > > > > Get.
>> > > > > > If
>> > > > > > > > you do a bunch of thread dumps in a row, where is the
>> > > lock-holding
>> > > > > > > thread?
>> > > > > > > > In Get or writing Increment... or waiting on sequence id?
>> > > > > > > >
>> > > > > > > > Is it possible you are contending on a counter post-upgrad=
e?
>> > Is
>> > > it
>> > > > > > > > possible that all these threads are trying to get to the
>> same
>> > row
>> > > > to
>> > > > > > > update
>> > > > > > > > it? Could the app behavior have changed?  Or are you
>> thinking
>> > > > > increment
>> > > > > > > > itself has slowed significantly?
>> > > > > > > >
>> > > > > > > > St.Ack
>> > > > > > > >
>> > > > > > > >
>> > > > > > > >
>> > > > > > > >
>> > > > > > > > > Thanks,
>> > > > > > > > >
>> > > > > > > > > Toshihiro Suzuki
>> > > > > > > > >
>> > > > > > > > >
>> > > > > > > > > 2015-09-09 0:05 GMT+09:00 Ted Yu <yuzhihong@gmail.com>:
>> > > > > > > > >
>> > > > > > > > > > In HRegion#increment(), we lock the row (not region):
>> > > > > > > > > >
>> > > > > > > > > >     try {
>> > > > > > > > > >       rowLock =3D getRowLock(row);
>> > > > > > > > > >
>> > > > > > > > > > Can you pastebin the complete stack trace ?
>> > > > > > > > > >
>> > > > > > > > > > Thanks
>> > > > > > > > > >
>> > > > > > > > > > On Tue, Sep 8, 2015 at 2:01 AM, =E9=88=B4=E6=9C=A8=E4=
=BF=8A=E8=A3=95 <
>> brfrn169@gmail.com>
>> > > > wrote:
>> > > > > > > > > >
>> > > > > > > > > > > Hi,
>> > > > > > > > > > >
>> > > > > > > > > > > We upgraded our cluster from CDH5.3.1(HBase0.98.6) t=
o
>> > > > > > > > > > CDH5.4.5(HBase1.0.0)
>> > > > > > > > > > > and we experience slowdown in increment operation.
>> > > > > > > > > > >
>> > > > > > > > > > > Here's an extract from thread dump of the
>> RegionServer of
>> > > our
>> > > > > > > > cluster:
>> > > > > > > > > > >
>> > > > > > > > > > > Thread 68
>> > > > > > > (RW.default.writeRpcServer.handler=3D15,queue=3D5,port=3D600=
20):
>> > > > > > > > > > >   State: BLOCKED
>> > > > > > > > > > >   Blocked count: 21689888
>> > > > > > > > > > >   Waited count: 39828360
>> > > > > > > > > > >   Blocked on java.util.LinkedList@3474e4b2
>> > > > > > > > > > >   Blocked by 63
>> > > > > > > > > (RW.default.writeRpcServer.handler=3D10,queue=3D0,port=
=3D60020)
>> > > > > > > > > > >   Stack:
>> > > > > > > > > > >     java.lang.Object.wait(Native Method)
>> > > > > > > > > > >
>> > > > > > > > > > >
>> > > > > > > > > > >
>> > > > > > > > > >
>> > > > > > > > >
>> > > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> org.apache.hadoop.hbase.regionserver.MultiVersionConsistencyControl.wait=
ForPreviousTransactionsComplete(MultiVersionConsistencyControl.java:224)
>> > > > > > > > > > >
>> > > > > > > > > > >
>> > > > > > > > > > >
>> > > > > > > > > >
>> > > > > > > > >
>> > > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> org.apache.hadoop.hbase.regionserver.MultiVersionConsistencyControl.wait=
ForPreviousTransactionsComplete(MultiVersionConsistencyControl.java:203)
>> > > > > > > > > > >
>> > > > > > > > > > >
>> > > > > > > > >
>> > > > > > >
>> > > > >
>> > >
>> org.apache.hadoop.hbase.regionserver.HRegion.increment(HRegion.java:6712=
)
>> > > > > > > > > > >
>> > > > > > > > > > >
>> > > > > > > > > > >
>> > > > > > > > > >
>> > > > > > > > >
>> > > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> org.apache.hadoop.hbase.regionserver.RSRpcServices.increment(RSRpcServic=
es.java:501)
>> > > > > > > > > > >
>> > > > > > > > > > >
>> > > > > > > > > > >
>> > > > > > > > > >
>> > > > > > > > >
>> > > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> org.apache.hadoop.hbase.regionserver.RSRpcServices.doNonAtomicRegionMuta=
tion(RSRpcServices.java:570)
>> > > > > > > > > > >
>> > > > > > > > > > >
>> > > > > > > > > > >
>> > > > > > > > > >
>> > > > > > > > >
>> > > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> org.apache.hadoop.hbase.regionserver.RSRpcServices.multi(RSRpcServices.j=
ava:1901)
>> > > > > > > > > > >
>> > > > > > > > > > >
>> > > > > > > > > > >
>> > > > > > > > > >
>> > > > > > > > >
>> > > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> org.apache.hadoop.hbase.protobuf.generated.ClientProtos$ClientService$2.=
callBlockingMethod(ClientProtos.java:31451)
>> > > > > > > > > > >
>> > > > > >  org.apache.hadoop.hbase.ipc.RpcServer.call(RpcServer.java:203=
5)
>> > > > > > > > > > >
>> > > > > >  org.apache.hadoop.hbase.ipc.CallRunner.run(CallRunner.java:10=
7)
>> > > > > > > > > > >
>> > > > > > > > > > >
>> > > > > > > > > >
>> > > > > > > > >
>> > > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>> org.apache.hadoop.hbase.ipc.RpcExecutor.consumerLoop(RpcExecutor.java:13=
0)
>> > > > > > > > > > >
>> > > > > > > >
>> > > > org.apache.hadoop.hbase.ipc.RpcExecutor$1.run(RpcExecutor.java:107=
)
>> > > > > > > > > > >     java.lang.Thread.run(Thread.java:745)
>> > > > > > > > > > >
>> > > > > > > > > > > There are many similar threads in the thread dump.
>> > > > > > > > > > >
>> > > > > > > > > > > I read the source code and I think this is caused by
>> > > changes
>> > > > of
>> > > > > > > > > > > MultiVersionConsistencyControl.
>> > > > > > > > > > > A region lock (not a row lock) seems to occur in
>> > > > > > > > > > > waitForPreviousTransactionsComplete().
>> > > > > > > > > > >
>> > > > > > > > > > >
>> > > > > > > > > > > Also we wrote performance test code for increment
>> > operation
>> > > > > that
>> > > > > > > > > included
>> > > > > > > > > > > 100 threads and ran it in local mode.
>> > > > > > > > > > >
>> > > > > > > > > > > The result is shown below:
>> > > > > > > > > > >
>> > > > > > > > > > > CDH5.3.1(HBase0.98.6)
>> > > > > > > > > > > Throughput(op/s): 12757, Latency(ms):
>> 7.975072509210629
>> > > > > > > > > > >
>> > > > > > > > > > > CDH5.4.5(HBase1.0.0)
>> > > > > > > > > > > Throughput(op/s): 2027, Latency(ms): 49.118401578687=
72
>> > > > > > > > > > >
>> > > > > > > > > > >
>> > > > > > > > > > > Thanks,
>> > > > > > > > > > >
>> > > > > > > > > > > Toshihiro Suzuki
>> > > > > > > > > > >
>> > > > > > > > > >
>> > > > > > > > >
>> > > > > > > >
>> > > > > > >
>> > > > > >
>> > > > >
>> > > >
>> > >
>> >
>>
>

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