You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@zookeeper.apache.org by "박영근 (Alex)" <al...@nexr.com> on 2011/08/30 03:50:38 UTC
NodeExistsException when creating a znode with sequential and
ephemeral mode
Hi, all
I met a problem of NodeExistsException when creating a znode with sequential
and ephemeral mode.
the number of total test was 6442314 and 797 errors had occurred.
The related log message is as in the following:
2011-08-27 16:26:17,559 - INFO [ProcessThread:-1:PrepRequestProcessor@407][]
- Got user-level KeeperException when processing sessionid:0x2320911802a0002
type:create cxid:0x1246d7 zxid:0xfffffffffffffffe txntype:unknown
reqpath:n/a Error
Path:/NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
Error:KeeperErrorCode = NodeExists for
/NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
The sequential number would be created by increasing parent's Cversion in
the PrepRequestProcess.
So, I guess that this problem was caused by inconsistency of parent znode.
Our test scenario is very aggressive:
The grinder agent sends a request of creating a znode of
CreateMode. SEQUENTIAL_EPHEMERAL.
three number of servers compose ensemble.
each NIC of server is down and up repeatedly;
NIC of server1 become down every one minute and sleeping for 9 seconds, then
up
NIC of server2 become down every 2 minute and sleeping for 9 seconds, then
up
NIC of server3 become down every 3 minute and sleeping for 9 seconds, then
up
while the probability of error occurrence is 0.0001 as mentioned above,
if the ZooKeeper cannot guarantee the consistency, it is a fatal.
Is there any idea or related issue?
thanks in advance.
alex.
Re: sync()
Posted by nicholas harteau <n...@hep.cat>.
Yeah, I just found that. Unfortunately we use the the zkperl bindings, which in turn use the single-threaded C client library, where sync() doesn't seem to be implemented.
I opened https://issues.apache.org/jira/browse/ZOOKEEPER-1167 to track.
On Aug 31, 2011, at 1:13 PM, Patrick Hunt wrote:
> In the c client it's called "zoo_async"
>
> Patrick
>
> On Wed, Aug 31, 2011 at 7:05 AM, nicholas harteau <n...@hep.cat> wrote:
>>
>> There don't seem to be any references to a sync() call in the C bindings, and I assume that the syncronous vs. asyncronous methods have more to do with threading than 'sync' in the ZK API sense.
>>
>> How does one invoke sync() from the C API?
>>
>> On Aug 30, 2011, at 1:18 PM, Patrick Hunt wrote:
>>
>>> All reads.
>>>
>>> On Tue, Aug 30, 2011 at 10:12 AM, Jordan Zimmerman
>>> <jz...@netflix.com> wrote:
>>>> Thanks - if I understand correctly, this only applies to reads. Is that
>>>> reads on data only (getData) or both data and a list of a Znode's children
>>>> (getChildren)?
>>>>
>>>> On 8/30/11 10:07 AM, "Patrick Hunt" <ph...@apache.org> wrote:
>>>>
>>>>> See this section of the programmers guide:
>>>>> http://zookeeper.apache.org/doc/r3.3.3/zookeeperProgrammers.html#ch_zkGuar
>>>>> antees
>>>>>
>>>>> specifically the section "Simultaneously Consistent Cross-Client Views"
>>>>>
>>>>> Patrick
>>>>>
>>>>> On Tue, Aug 30, 2011 at 9:52 AM, Jordan Zimmerman
>>>>> <jz...@netflix.com> wrote:
>>>>>> When/why does sync() need to be called? I've searched the archive and
>>>>>> the
>>>>>> docs are non-existent. Any examples would be appreciated.
>>>>>>
>>>>>> -JZ
>>>>>>
>>>>>>
>>>>>
>>>>
>>>>
>>
>> --
>> n@hep.cat (>^-^)>
>>
>>
>>
>>
>>
--
n@hep.cat l^o
Re: sync()
Posted by Patrick Hunt <ph...@apache.org>.
In the c client it's called "zoo_async"
Patrick
On Wed, Aug 31, 2011 at 7:05 AM, nicholas harteau <n...@hep.cat> wrote:
>
> There don't seem to be any references to a sync() call in the C bindings, and I assume that the syncronous vs. asyncronous methods have more to do with threading than 'sync' in the ZK API sense.
>
> How does one invoke sync() from the C API?
>
> On Aug 30, 2011, at 1:18 PM, Patrick Hunt wrote:
>
>> All reads.
>>
>> On Tue, Aug 30, 2011 at 10:12 AM, Jordan Zimmerman
>> <jz...@netflix.com> wrote:
>>> Thanks - if I understand correctly, this only applies to reads. Is that
>>> reads on data only (getData) or both data and a list of a Znode's children
>>> (getChildren)?
>>>
>>> On 8/30/11 10:07 AM, "Patrick Hunt" <ph...@apache.org> wrote:
>>>
>>>> See this section of the programmers guide:
>>>> http://zookeeper.apache.org/doc/r3.3.3/zookeeperProgrammers.html#ch_zkGuar
>>>> antees
>>>>
>>>> specifically the section "Simultaneously Consistent Cross-Client Views"
>>>>
>>>> Patrick
>>>>
>>>> On Tue, Aug 30, 2011 at 9:52 AM, Jordan Zimmerman
>>>> <jz...@netflix.com> wrote:
>>>>> When/why does sync() need to be called? I've searched the archive and
>>>>> the
>>>>> docs are non-existent. Any examples would be appreciated.
>>>>>
>>>>> -JZ
>>>>>
>>>>>
>>>>
>>>
>>>
>
> --
> n@hep.cat (>^-^)>
>
>
>
>
>
Re: sync()
Posted by nicholas harteau <n...@hep.cat>.
There don't seem to be any references to a sync() call in the C bindings, and I assume that the syncronous vs. asyncronous methods have more to do with threading than 'sync' in the ZK API sense.
How does one invoke sync() from the C API?
On Aug 30, 2011, at 1:18 PM, Patrick Hunt wrote:
> All reads.
>
> On Tue, Aug 30, 2011 at 10:12 AM, Jordan Zimmerman
> <jz...@netflix.com> wrote:
>> Thanks - if I understand correctly, this only applies to reads. Is that
>> reads on data only (getData) or both data and a list of a Znode's children
>> (getChildren)?
>>
>> On 8/30/11 10:07 AM, "Patrick Hunt" <ph...@apache.org> wrote:
>>
>>> See this section of the programmers guide:
>>> http://zookeeper.apache.org/doc/r3.3.3/zookeeperProgrammers.html#ch_zkGuar
>>> antees
>>>
>>> specifically the section "Simultaneously Consistent Cross-Client Views"
>>>
>>> Patrick
>>>
>>> On Tue, Aug 30, 2011 at 9:52 AM, Jordan Zimmerman
>>> <jz...@netflix.com> wrote:
>>>> When/why does sync() need to be called? I've searched the archive and
>>>> the
>>>> docs are non-existent. Any examples would be appreciated.
>>>>
>>>> -JZ
>>>>
>>>>
>>>
>>
>>
--
n@hep.cat (>^-^)>
Re: sync()
Posted by Patrick Hunt <ph...@apache.org>.
All reads.
On Tue, Aug 30, 2011 at 10:12 AM, Jordan Zimmerman
<jz...@netflix.com> wrote:
> Thanks - if I understand correctly, this only applies to reads. Is that
> reads on data only (getData) or both data and a list of a Znode's children
> (getChildren)?
>
> On 8/30/11 10:07 AM, "Patrick Hunt" <ph...@apache.org> wrote:
>
>>See this section of the programmers guide:
>>http://zookeeper.apache.org/doc/r3.3.3/zookeeperProgrammers.html#ch_zkGuar
>>antees
>>
>>specifically the section "Simultaneously Consistent Cross-Client Views"
>>
>>Patrick
>>
>>On Tue, Aug 30, 2011 at 9:52 AM, Jordan Zimmerman
>><jz...@netflix.com> wrote:
>>> When/why does sync() need to be called? I've searched the archive and
>>>the
>>> docs are non-existent. Any examples would be appreciated.
>>>
>>> -JZ
>>>
>>>
>>
>
>
Re: sync()
Posted by Jordan Zimmerman <jz...@netflix.com>.
Thanks - if I understand correctly, this only applies to reads. Is that
reads on data only (getData) or both data and a list of a Znode's children
(getChildren)?
On 8/30/11 10:07 AM, "Patrick Hunt" <ph...@apache.org> wrote:
>See this section of the programmers guide:
>http://zookeeper.apache.org/doc/r3.3.3/zookeeperProgrammers.html#ch_zkGuar
>antees
>
>specifically the section "Simultaneously Consistent Cross-Client Views"
>
>Patrick
>
>On Tue, Aug 30, 2011 at 9:52 AM, Jordan Zimmerman
><jz...@netflix.com> wrote:
>> When/why does sync() need to be called? I've searched the archive and
>>the
>> docs are non-existent. Any examples would be appreciated.
>>
>> -JZ
>>
>>
>
Re: sync()
Posted by Patrick Hunt <ph...@apache.org>.
See this section of the programmers guide:
http://zookeeper.apache.org/doc/r3.3.3/zookeeperProgrammers.html#ch_zkGuarantees
specifically the section "Simultaneously Consistent Cross-Client Views"
Patrick
On Tue, Aug 30, 2011 at 9:52 AM, Jordan Zimmerman
<jz...@netflix.com> wrote:
> When/why does sync() need to be called? I've searched the archive and the
> docs are non-existent. Any examples would be appreciated.
>
> -JZ
>
>
Re: NodeExistsException when creating a znode with sequential and
ephemeral mode
Posted by "박영근 (Alex)" <al...@nexr.com>.
Camille
We applied the patch (ZOOKEEPER-1046-for333) to our SUT.
There was no error.
Thanks
alex
2011년 8월 30일 오전 11:19, 박영근(Alex) <al...@nexr.com>님의 말:
> We used 3.3.3.
>
> We will check out the latest code.
>
> Thanks Camille.
>
> Alex
>
>
> 2011/8/30 Camille Fournier <ca...@apache.org>
>
>> More specifically, we fixed this for the upcoming release:
>> https://issues.apache.org/jira/browse/ZOOKEEPER-1046
>>
>> You can try checking out the latest code and building it, should fix
>> your error. I believe 3.3.4 will be released in a week or two.
>>
>> c
>>
>> On Mon, Aug 29, 2011 at 9:56 PM, Camille Fournier <ca...@apache.org>
>> wrote:
>> > What version of ZK were you using?
>> >
>> > On Mon, Aug 29, 2011 at 9:50 PM, 박영근(Alex) <al...@nexr.com> wrote:
>> >> Hi, all
>> >>
>> >> I met a problem of NodeExistsException when creating a znode with
>> sequential
>> >> and ephemeral mode.
>> >> the number of total test was 6442314 and 797 errors had occurred.
>> >>
>> >> The related log message is as in the following:
>> >> 2011-08-27 16:26:17,559 - INFO
>> [ProcessThread:-1:PrepRequestProcessor@407][]
>> >> - Got user-level KeeperException when processing
>> sessionid:0x2320911802a0002
>> >> type:create cxid:0x1246d7 zxid:0xfffffffffffffffe txntype:unknown
>> >> reqpath:n/a Error
>> >> Path:/NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
>> >> Error:KeeperErrorCode = NodeExists for
>> >> /NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
>> >>
>> >> The sequential number would be created by increasing parent's Cversion
>> in
>> >> the PrepRequestProcess.
>> >> So, I guess that this problem was caused by inconsistency of parent
>> znode.
>> >>
>> >> Our test scenario is very aggressive:
>> >> The grinder agent sends a request of creating a znode of
>> >> CreateMode. SEQUENTIAL_EPHEMERAL.
>> >> three number of servers compose ensemble.
>> >> each NIC of server is down and up repeatedly;
>> >> NIC of server1 become down every one minute and sleeping for 9 seconds,
>> then
>> >> up
>> >> NIC of server2 become down every 2 minute and sleeping for 9 seconds,
>> then
>> >> up
>> >> NIC of server3 become down every 3 minute and sleeping for 9 seconds,
>> then
>> >> up
>> >>
>> >> while the probability of error occurrence is 0.0001 as mentioned above,
>> >> if the ZooKeeper cannot guarantee the consistency, it is a fatal.
>> >>
>> >> Is there any idea or related issue?
>> >>
>> >> thanks in advance.
>> >>
>> >> alex.
>> >>
>> >
>>
>
>
Re: NodeExistsException when creating a znode with sequential and
ephemeral mode
Posted by "박영근 (Alex)" <al...@nexr.com>.
Camille
We applied the patch (ZOOKEEPER-1046-for333) to our SUT.
There was no error.
Thanks
alex
2011년 8월 30일 오전 11:19, 박영근(Alex) <al...@nexr.com>님의 말:
> We used 3.3.3.
>
> We will check out the latest code.
>
> Thanks Camille.
>
> Alex
>
>
> 2011/8/30 Camille Fournier <ca...@apache.org>
>
>> More specifically, we fixed this for the upcoming release:
>> https://issues.apache.org/jira/browse/ZOOKEEPER-1046
>>
>> You can try checking out the latest code and building it, should fix
>> your error. I believe 3.3.4 will be released in a week or two.
>>
>> c
>>
>> On Mon, Aug 29, 2011 at 9:56 PM, Camille Fournier <ca...@apache.org>
>> wrote:
>> > What version of ZK were you using?
>> >
>> > On Mon, Aug 29, 2011 at 9:50 PM, 박영근(Alex) <al...@nexr.com> wrote:
>> >> Hi, all
>> >>
>> >> I met a problem of NodeExistsException when creating a znode with
>> sequential
>> >> and ephemeral mode.
>> >> the number of total test was 6442314 and 797 errors had occurred.
>> >>
>> >> The related log message is as in the following:
>> >> 2011-08-27 16:26:17,559 - INFO
>> [ProcessThread:-1:PrepRequestProcessor@407][]
>> >> - Got user-level KeeperException when processing
>> sessionid:0x2320911802a0002
>> >> type:create cxid:0x1246d7 zxid:0xfffffffffffffffe txntype:unknown
>> >> reqpath:n/a Error
>> >> Path:/NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
>> >> Error:KeeperErrorCode = NodeExists for
>> >> /NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
>> >>
>> >> The sequential number would be created by increasing parent's Cversion
>> in
>> >> the PrepRequestProcess.
>> >> So, I guess that this problem was caused by inconsistency of parent
>> znode.
>> >>
>> >> Our test scenario is very aggressive:
>> >> The grinder agent sends a request of creating a znode of
>> >> CreateMode. SEQUENTIAL_EPHEMERAL.
>> >> three number of servers compose ensemble.
>> >> each NIC of server is down and up repeatedly;
>> >> NIC of server1 become down every one minute and sleeping for 9 seconds,
>> then
>> >> up
>> >> NIC of server2 become down every 2 minute and sleeping for 9 seconds,
>> then
>> >> up
>> >> NIC of server3 become down every 3 minute and sleeping for 9 seconds,
>> then
>> >> up
>> >>
>> >> while the probability of error occurrence is 0.0001 as mentioned above,
>> >> if the ZooKeeper cannot guarantee the consistency, it is a fatal.
>> >>
>> >> Is there any idea or related issue?
>> >>
>> >> thanks in advance.
>> >>
>> >> alex.
>> >>
>> >
>>
>
>
sync()
Posted by Jordan Zimmerman <jz...@netflix.com>.
When/why does sync() need to be called? I've searched the archive and the
docs are non-existent. Any examples would be appreciated.
-JZ
Re: NodeExistsException when creating a znode with sequential and
ephemeral mode
Posted by "박영근 (Alex)" <al...@nexr.com>.
We used 3.3.3.
We will check out the latest code.
Thanks Camille.
Alex
2011/8/30 Camille Fournier <ca...@apache.org>
> More specifically, we fixed this for the upcoming release:
> https://issues.apache.org/jira/browse/ZOOKEEPER-1046
>
> You can try checking out the latest code and building it, should fix
> your error. I believe 3.3.4 will be released in a week or two.
>
> c
>
> On Mon, Aug 29, 2011 at 9:56 PM, Camille Fournier <ca...@apache.org>
> wrote:
> > What version of ZK were you using?
> >
> > On Mon, Aug 29, 2011 at 9:50 PM, 박영근(Alex) <al...@nexr.com> wrote:
> >> Hi, all
> >>
> >> I met a problem of NodeExistsException when creating a znode with
> sequential
> >> and ephemeral mode.
> >> the number of total test was 6442314 and 797 errors had occurred.
> >>
> >> The related log message is as in the following:
> >> 2011-08-27 16:26:17,559 - INFO
> [ProcessThread:-1:PrepRequestProcessor@407][]
> >> - Got user-level KeeperException when processing
> sessionid:0x2320911802a0002
> >> type:create cxid:0x1246d7 zxid:0xfffffffffffffffe txntype:unknown
> >> reqpath:n/a Error
> >> Path:/NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
> >> Error:KeeperErrorCode = NodeExists for
> >> /NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
> >>
> >> The sequential number would be created by increasing parent's Cversion
> in
> >> the PrepRequestProcess.
> >> So, I guess that this problem was caused by inconsistency of parent
> znode.
> >>
> >> Our test scenario is very aggressive:
> >> The grinder agent sends a request of creating a znode of
> >> CreateMode. SEQUENTIAL_EPHEMERAL.
> >> three number of servers compose ensemble.
> >> each NIC of server is down and up repeatedly;
> >> NIC of server1 become down every one minute and sleeping for 9 seconds,
> then
> >> up
> >> NIC of server2 become down every 2 minute and sleeping for 9 seconds,
> then
> >> up
> >> NIC of server3 become down every 3 minute and sleeping for 9 seconds,
> then
> >> up
> >>
> >> while the probability of error occurrence is 0.0001 as mentioned above,
> >> if the ZooKeeper cannot guarantee the consistency, it is a fatal.
> >>
> >> Is there any idea or related issue?
> >>
> >> thanks in advance.
> >>
> >> alex.
> >>
> >
>
Re: NodeExistsException when creating a znode with sequential and
ephemeral mode
Posted by "박영근 (Alex)" <al...@nexr.com>.
We used 3.3.3.
We will check out the latest code.
Thanks Camille.
Alex
2011/8/30 Camille Fournier <ca...@apache.org>
> More specifically, we fixed this for the upcoming release:
> https://issues.apache.org/jira/browse/ZOOKEEPER-1046
>
> You can try checking out the latest code and building it, should fix
> your error. I believe 3.3.4 will be released in a week or two.
>
> c
>
> On Mon, Aug 29, 2011 at 9:56 PM, Camille Fournier <ca...@apache.org>
> wrote:
> > What version of ZK were you using?
> >
> > On Mon, Aug 29, 2011 at 9:50 PM, 박영근(Alex) <al...@nexr.com> wrote:
> >> Hi, all
> >>
> >> I met a problem of NodeExistsException when creating a znode with
> sequential
> >> and ephemeral mode.
> >> the number of total test was 6442314 and 797 errors had occurred.
> >>
> >> The related log message is as in the following:
> >> 2011-08-27 16:26:17,559 - INFO
> [ProcessThread:-1:PrepRequestProcessor@407][]
> >> - Got user-level KeeperException when processing
> sessionid:0x2320911802a0002
> >> type:create cxid:0x1246d7 zxid:0xfffffffffffffffe txntype:unknown
> >> reqpath:n/a Error
> >> Path:/NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
> >> Error:KeeperErrorCode = NodeExists for
> >> /NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
> >>
> >> The sequential number would be created by increasing parent's Cversion
> in
> >> the PrepRequestProcess.
> >> So, I guess that this problem was caused by inconsistency of parent
> znode.
> >>
> >> Our test scenario is very aggressive:
> >> The grinder agent sends a request of creating a znode of
> >> CreateMode. SEQUENTIAL_EPHEMERAL.
> >> three number of servers compose ensemble.
> >> each NIC of server is down and up repeatedly;
> >> NIC of server1 become down every one minute and sleeping for 9 seconds,
> then
> >> up
> >> NIC of server2 become down every 2 minute and sleeping for 9 seconds,
> then
> >> up
> >> NIC of server3 become down every 3 minute and sleeping for 9 seconds,
> then
> >> up
> >>
> >> while the probability of error occurrence is 0.0001 as mentioned above,
> >> if the ZooKeeper cannot guarantee the consistency, it is a fatal.
> >>
> >> Is there any idea or related issue?
> >>
> >> thanks in advance.
> >>
> >> alex.
> >>
> >
>
Re: NodeExistsException when creating a znode with sequential and
ephemeral mode
Posted by Camille Fournier <ca...@apache.org>.
More specifically, we fixed this for the upcoming release:
https://issues.apache.org/jira/browse/ZOOKEEPER-1046
You can try checking out the latest code and building it, should fix
your error. I believe 3.3.4 will be released in a week or two.
c
On Mon, Aug 29, 2011 at 9:56 PM, Camille Fournier <ca...@apache.org> wrote:
> What version of ZK were you using?
>
> On Mon, Aug 29, 2011 at 9:50 PM, 박영근(Alex) <al...@nexr.com> wrote:
>> Hi, all
>>
>> I met a problem of NodeExistsException when creating a znode with sequential
>> and ephemeral mode.
>> the number of total test was 6442314 and 797 errors had occurred.
>>
>> The related log message is as in the following:
>> 2011-08-27 16:26:17,559 - INFO [ProcessThread:-1:PrepRequestProcessor@407][]
>> - Got user-level KeeperException when processing sessionid:0x2320911802a0002
>> type:create cxid:0x1246d7 zxid:0xfffffffffffffffe txntype:unknown
>> reqpath:n/a Error
>> Path:/NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
>> Error:KeeperErrorCode = NodeExists for
>> /NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
>>
>> The sequential number would be created by increasing parent's Cversion in
>> the PrepRequestProcess.
>> So, I guess that this problem was caused by inconsistency of parent znode.
>>
>> Our test scenario is very aggressive:
>> The grinder agent sends a request of creating a znode of
>> CreateMode. SEQUENTIAL_EPHEMERAL.
>> three number of servers compose ensemble.
>> each NIC of server is down and up repeatedly;
>> NIC of server1 become down every one minute and sleeping for 9 seconds, then
>> up
>> NIC of server2 become down every 2 minute and sleeping for 9 seconds, then
>> up
>> NIC of server3 become down every 3 minute and sleeping for 9 seconds, then
>> up
>>
>> while the probability of error occurrence is 0.0001 as mentioned above,
>> if the ZooKeeper cannot guarantee the consistency, it is a fatal.
>>
>> Is there any idea or related issue?
>>
>> thanks in advance.
>>
>> alex.
>>
>
Re: NodeExistsException when creating a znode with sequential and
ephemeral mode
Posted by Camille Fournier <ca...@apache.org>.
More specifically, we fixed this for the upcoming release:
https://issues.apache.org/jira/browse/ZOOKEEPER-1046
You can try checking out the latest code and building it, should fix
your error. I believe 3.3.4 will be released in a week or two.
c
On Mon, Aug 29, 2011 at 9:56 PM, Camille Fournier <ca...@apache.org> wrote:
> What version of ZK were you using?
>
> On Mon, Aug 29, 2011 at 9:50 PM, 박영근(Alex) <al...@nexr.com> wrote:
>> Hi, all
>>
>> I met a problem of NodeExistsException when creating a znode with sequential
>> and ephemeral mode.
>> the number of total test was 6442314 and 797 errors had occurred.
>>
>> The related log message is as in the following:
>> 2011-08-27 16:26:17,559 - INFO [ProcessThread:-1:PrepRequestProcessor@407][]
>> - Got user-level KeeperException when processing sessionid:0x2320911802a0002
>> type:create cxid:0x1246d7 zxid:0xfffffffffffffffe txntype:unknown
>> reqpath:n/a Error
>> Path:/NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
>> Error:KeeperErrorCode = NodeExists for
>> /NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
>>
>> The sequential number would be created by increasing parent's Cversion in
>> the PrepRequestProcess.
>> So, I guess that this problem was caused by inconsistency of parent znode.
>>
>> Our test scenario is very aggressive:
>> The grinder agent sends a request of creating a znode of
>> CreateMode. SEQUENTIAL_EPHEMERAL.
>> three number of servers compose ensemble.
>> each NIC of server is down and up repeatedly;
>> NIC of server1 become down every one minute and sleeping for 9 seconds, then
>> up
>> NIC of server2 become down every 2 minute and sleeping for 9 seconds, then
>> up
>> NIC of server3 become down every 3 minute and sleeping for 9 seconds, then
>> up
>>
>> while the probability of error occurrence is 0.0001 as mentioned above,
>> if the ZooKeeper cannot guarantee the consistency, it is a fatal.
>>
>> Is there any idea or related issue?
>>
>> thanks in advance.
>>
>> alex.
>>
>
Re: NodeExistsException when creating a znode with sequential and
ephemeral mode
Posted by Camille Fournier <ca...@apache.org>.
What version of ZK were you using?
On Mon, Aug 29, 2011 at 9:50 PM, 박영근(Alex) <al...@nexr.com> wrote:
> Hi, all
>
> I met a problem of NodeExistsException when creating a znode with sequential
> and ephemeral mode.
> the number of total test was 6442314 and 797 errors had occurred.
>
> The related log message is as in the following:
> 2011-08-27 16:26:17,559 - INFO [ProcessThread:-1:PrepRequestProcessor@407][]
> - Got user-level KeeperException when processing sessionid:0x2320911802a0002
> type:create cxid:0x1246d7 zxid:0xfffffffffffffffe txntype:unknown
> reqpath:n/a Error
> Path:/NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
> Error:KeeperErrorCode = NodeExists for
> /NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
>
> The sequential number would be created by increasing parent's Cversion in
> the PrepRequestProcess.
> So, I guess that this problem was caused by inconsistency of parent znode.
>
> Our test scenario is very aggressive:
> The grinder agent sends a request of creating a znode of
> CreateMode. SEQUENTIAL_EPHEMERAL.
> three number of servers compose ensemble.
> each NIC of server is down and up repeatedly;
> NIC of server1 become down every one minute and sleeping for 9 seconds, then
> up
> NIC of server2 become down every 2 minute and sleeping for 9 seconds, then
> up
> NIC of server3 become down every 3 minute and sleeping for 9 seconds, then
> up
>
> while the probability of error occurrence is 0.0001 as mentioned above,
> if the ZooKeeper cannot guarantee the consistency, it is a fatal.
>
> Is there any idea or related issue?
>
> thanks in advance.
>
> alex.
>
Re: NodeExistsException when creating a znode with sequential and
ephemeral mode
Posted by Camille Fournier <ca...@apache.org>.
What version of ZK were you using?
On Mon, Aug 29, 2011 at 9:50 PM, 박영근(Alex) <al...@nexr.com> wrote:
> Hi, all
>
> I met a problem of NodeExistsException when creating a znode with sequential
> and ephemeral mode.
> the number of total test was 6442314 and 797 errors had occurred.
>
> The related log message is as in the following:
> 2011-08-27 16:26:17,559 - INFO [ProcessThread:-1:PrepRequestProcessor@407][]
> - Got user-level KeeperException when processing sessionid:0x2320911802a0002
> type:create cxid:0x1246d7 zxid:0xfffffffffffffffe txntype:unknown
> reqpath:n/a Error
> Path:/NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
> Error:KeeperErrorCode = NodeExists for
> /NexR/MasteElection/__rwLock/readLock-lssm07-0005967078
>
> The sequential number would be created by increasing parent's Cversion in
> the PrepRequestProcess.
> So, I guess that this problem was caused by inconsistency of parent znode.
>
> Our test scenario is very aggressive:
> The grinder agent sends a request of creating a znode of
> CreateMode. SEQUENTIAL_EPHEMERAL.
> three number of servers compose ensemble.
> each NIC of server is down and up repeatedly;
> NIC of server1 become down every one minute and sleeping for 9 seconds, then
> up
> NIC of server2 become down every 2 minute and sleeping for 9 seconds, then
> up
> NIC of server3 become down every 3 minute and sleeping for 9 seconds, then
> up
>
> while the probability of error occurrence is 0.0001 as mentioned above,
> if the ZooKeeper cannot guarantee the consistency, it is a fatal.
>
> Is there any idea or related issue?
>
> thanks in advance.
>
> alex.
>