Re: Zookeeper: Testing Questions

[GANESH CHANDRASEKARAN (RIT Student)]

> Hi all,
>
> I am trying to do some tests to see how long it takes for Zookeeper to
> write various sizes of data on each znode. I am using PHP-API from
> https://github.com/andreiz/php-zookeeper. I have 2 questions:
>
> 1. How do I write 4000 bytes - 1MB of data on each znode? My php client
> starts acting up beyond 4000 bytes and I am not able to edit the client. I
> am using VIM on Xubuntu VM 32 bit.
>
> 2. I have a 3 node (N1, N2 (leader), N3) cluster set-up. When I perform a
> single write I see weird timings on the zookeeper log files.
>
> Lets say I do a write to N1. I get the following result on the N1 and N2's
> log files:
>
> N1----------------
>
> 2014-05-07 10:51:01,732 [myid:1] - DEBUG
> [QuorumPeer[myid=1]/0:0:0:0:0:0:0:0:2181:CommitProcessor@161] -
> Committing request:: sessionid:0x145be8a7f4b0041 type:create
> cxid:0x536a4857 zxid:0x100000196 txntype:1 reqpath:n/a
> 2014-05-07 10:51:01,733 [myid:1] - DEBUG
> [CommitProcessor:1:FinalRequestProcessor@88] - Processing request::
> sessionid:0x145be8a7f4b0041 type:create cxid:0x536a4857 zxid:0x100000196
> txntype:1 reqpath:/test--10
> 2014-05-07 10:51:01,734 [myid:1] - DEBUG
> [CommitProcessor:1:FinalRequestProcessor@160] -
> sessionid:0x145be8a7f4b0041 type:create cxid:0x536a4857 zxid:0x100000196
> txntype:1 reqpath:/test--10
>
>
> N2----------------
>
> 2014-05-07 10:51:01,705 [myid:2] - DEBUG [ProcessThread(sid:2
> cport:-1)::CommitProcessor@171] - Processing request::
> sessionid:0x145be8a7f4b0041 type:create cxid:0x536a4857 zxid:0x100000196
> txntype:1 reqpath:n/a
> 2014-05-07 10:51:01,705 [myid:2] - DEBUG [ProcessThread(sid:2
> cport:-1)::Leader@768] - Proposing:: sessionid:0x145be8a7f4b0041
> type:create cxid:0x536a4857 zxid:0x100000196 txntype:1 reqpath:n/a
> 2014-05-07 10:51:01,740 [myid:2] - DEBUG [LearnerHandler-/10.22.70.20:47250
> :CommitProcessor@161] - Committing request:: sessionid:0x145be8a7f4b0041
> type:create cxid:0x536a4857 zxid:0x100000196 txntype:1 reqpath:n/a
> 2014-05-07 10:51:01,741 [myid:2] - DEBUG
> [CommitProcessor:2:FinalRequestProcessor@88] - Processing request::
> sessionid:0x145be8a7f4b0041 type:create cxid:0x536a4857 zxid:0x100000196
> txntype:1 reqpath:n/a
>
> How is the operation first logged in N2 before logging in N1? This does
> not happen all the time, the order of logging for a single operation is
> always different in various write operations. Anyone knows why this could
> be happening? My question regarding the timing is only for logging. I know
> all the operations in zookeeper are ordered so do not confuse it with that.
> Also, the timings on my zookeeper servers are synchronized.
>
> Let me know if you need any more information!
>
> Many thanks,
> Ganesh Chandrasekaran
>
>