Another think you could do is to make snapCount very large so that snapshots 
are created infrequently. But, let me step back and ask you why you think ZK is 
a good fit for your project. It isn't clear to me that your case is a good one 
for ZK.

-Flavio

 
> On 16 Apr 2015, at 11:01, Dejan Markic <[email protected]> wrote:
> 
> Hello!
> 
> Log seems to be always 67.108.880 bytes.
> Snapshots are currently between 30-40MB. Snapshot is created almost every 
> minute.
> Yes, data durability is not important at all. Once the session ends (it may 
> last between 0 and few minutes, average around 1-2 minutes maybe), I don't 
> need it anymore. I regulary remove  nodes that are not changed for more than 
> 10 minutes.
> I even recieve updates for sessions, so even if ZK looses data, I would get 
> it back after few minutes.
> 
> Thanks!
> 
> Kind regards,
> Dejan
> 
> 
> -----Original Message-----
> From: Flavio Junqueira [mailto:[email protected]] 
> Sent: Thursday, April 16, 2015 11:49 AM
> To: [email protected]
> Subject: Re: Transaction logs and snapshots
> 
> Hi Dejan,
> For a typical ZK application, granularity of hours is more than enough, since 
> it is supposed to be an infrequent background task. In your case, it sounds 
> like durability isn't an important property because if it is you shouldn't be 
> getting rid of disk data this fast. I'm also wondering about the amount of 
> data you're generating. What's the size of your snapshots and txn logs?
> -Flavio 
> 
> 
>     On Thursday, April 16, 2015 10:26 AM, Dejan Markic 
> <[email protected]> wrote:
> 
> 
> 
> Hello Flavio!
> 
> Would that mean, that zkCleanup.sh would not be needed? 
> PurgeInterval is minimum 1 hour? Why is it so high?
> 
> Thanks!
> 
> Kind regards,
> Dejan Markic
> 
> 
> -----Original Message-----
> From: Flavio Junqueira [mailto:[email protected]] 
> Sent: Thursday, April 16, 2015 11:15 AM
> To: [email protected]
> Subject: Re: Transaction logs and snapshots
> 
> Hi Dejan,
> Check if the autopurge feature solves your problem:
> http://zookeeper.apache.org/doc/r3.4.6/zookeeperAdmin.html#sc_advancedConfiguration
> 
> -Flavio 
> 
> 
>     On Thursday, April 16, 2015 9:17 AM, Dejan Markic 
> <[email protected]> wrote:
>   
> 
> 
> Hello all!
> 
> We are running 3 ZK servers in ensemble, and ZK is processing a lot of 
> commands per seconds. There are probably around 300 nodes 
> created/checked/set/get per second.
> Since we have only information about live sessions we handle in ZK, we don't 
> need any data persistency - eg: we can stop all nodes, clean all transaction 
> logs/snapshots, and start them up again, without any issues.
> Since we have a lot of requests/changes, we have moved dataDir onto ramdisk, 
> so we have no problems with disk IOPS, etc.
> Is there a way, to minimze the usage of snapshots/logs so ramdisk would not 
> get filled up? It happens that transaction logs/snapshots grow so large, that 
> we run out of space on ramdisk.
> We issue >/usr/share/zookeeper/bin/zkCleanup.sh -n 3< every 2 minutes, so 
> this should cleanup the dataDir quite often. Why is >count number of 
> snapshots/logs to keep< limited to 3 and not below?
> I assume, in my setup, I don't even need snapshots/logs to be stored after 
> they are not actively needed? 
> So my basic questions are:
> - can I somehow get rid of snapshot/logs sooner, more often ... ?
> - when is snapshot created? Can it be created sooner, so it would be smaller? 
> - Is it possible to get rid of snapshot/logs all together?
> 
> Thank you for all your inputs and kind regards, Dejan Markic
> 
> 
>   
> 
> 
> 
> 

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