Exactly, this doesn't make sense. I filed an enhancement to have this in GW a while ago.
On Tue, Feb 2, 2016 at 8:48 AM, Pramod Immaneni <[email protected]> wrote: > Yogi, > > kill is not an orderly shutdown, who will clean the state? > > On Tue, Feb 2, 2016 at 8:38 AM, Yogi Devendra <[email protected]> > wrote: > > > I would prefer to have an additional argument during application launch > on > > dtcli. > > > > Say, --preserve-kill-state true . > > > > Basically, platform should be able to do the clean-up activity if the > > application is invoked with certain flag. > > > > Test apps can set this flag to clear the data on kill. Production apps > can > > set this flag to keep the data on kill. > > > > Shutdown should always preserve the state. But, for kill / > forced-shutdown > > user might prefer to clear the state. > > > > ~ Yogi > > > > On 2 February 2016 at 21:53, Amol Kekre <[email protected]> wrote: > > > >> > >> Can we include a script in our github (util?) that simply deletes these > >> files upon application being killed, given an app-id. The admin will > need > >> to run this script. Auto-deleting will be bad as a lot of users, > including > >> those in production today need to restart using those files. The > >> knowledge/desire to restart post failure is outside the app and hence > >> technically the script should be explicitly user invoked > >> > >> Thks, > >> Amol > >> > >> > >> On Tue, Feb 2, 2016 at 6:12 AM, Pramod Immaneni <[email protected] > > > >> wrote: > >> > >>> Hi Venkat, > >>> > >>> There are typically a small number of outstanding checkpoint files per > >>> operator, as newer checkpoints are created old ones are automatically > >>> deleted by the application when it determines that state is no longer > >>> needed. When an application stops/killed the last checkpoints remain. > >>> There > >>> is also a benefit to that since a new application can be restarted to > >>> continue from those checkpoints instead of starting all the way from > the > >>> beginning and this is useful in some cases. But if you are always > >>> starting > >>> your application from scratch yes you can delete the checkpoints of > older > >>> applications that are no longer running. > >>> > >>> Thanks > >>> > >>> On Mon, Feb 1, 2016 at 10:19 PM, Kottapalli, Venkatesh < > >>> [email protected]> wrote: > >>> > >>> > Hi, > >>> > > >>> > Now that this has been discussed, Will the checkpointed data > be > >>> > purged when we kill the application forcefully? In our current > usage, > >>> we > >>> > forcefully kill the app after it processes a certain batch of data. I > >>> see > >>> > these small files are created under (user/datatorrent) directory and > >>> not > >>> > removed. > >>> > > >>> > Another scenario, when some of the containers keep failing, > we > >>> > have observed this state where the data is continuously checkpointed > >>> into > >>> > small files. When we kill the app, the data will be there. > >>> > > >>> > We have received concerns saying this is impacting namenode > >>> > performance since these small files are stored in HDFS. So we > manually > >>> > remove these checkpointed data at regular intervals. > >>> > > >>> > -Venkatesh > >>> > > >>> > -----Original Message----- > >>> > From: Amol Kekre [mailto:[email protected]] > >>> > Sent: Monday, February 01, 2016 7:49 AM > >>> > To: [email protected]; [email protected] > >>> > Subject: Re: Possibility of saving checkpoints on other distributed > >>> > filesystems > >>> > > >>> > Aniruddha, > >>> > We have not heard this request from users yet. It may be because our > >>> > checkpointing has a purge, i.e. the small files are not left over. > >>> Small > >>> > file problem has been there in Hadoop and relates to storing small > >>> files in > >>> > Hadoop for a longer time (more likely forever). > >>> > > >>> > Thks, > >>> > Amol > >>> > > >>> > > >>> > On Mon, Feb 1, 2016 at 6:05 AM, Aniruddha Thombare < > >>> > [email protected]> wrote: > >>> > > >>> > > Hi Community, > >>> > > > >>> > > Or Let me say BigFoots, do you think this feature should be > >>> available? > >>> > > > >>> > > The reason to bring this up was discussed in the start of this > >>> thread as: > >>> > > > >>> > > This is with the intention to recover the applications faster and > do > >>> > > away > >>> > > > with HDFS's small files problem as described here: > >>> > > > http://blog.cloudera.com/blog/2009/02/the-small-files-problem/ > >>> > > > > >>> > > > > >>> > > > >>> http://snowplowanalytics.com/blog/2013/05/30/dealing-with-hadoops-smal > >>> > > l-files-problem/ > >>> > > > > >>> http://inquidia.com/news-and-info/working-small-files-hadoop-part-1 > >>> > > > If we could save checkpoints in some other distributed file > system > >>> > > > (or even a HA NAS box) geared for small files, we could achieve - > >>> > > > > >>> > > > - Better performance of NN & HDFS for the production usage > >>> (read: > >>> > > > production data I/O & not temp files) > >>> > > > > >>> > > > > >>> > > > - Faster application recovery in case of planned shutdown / > >>> > unplanned > >>> > > > restarts > >>> > > > > >>> > > > If you feel the need of this feature, please cast your opinions > and > >>> > > > ideas > >>> > > so that it can be converted in a jira. > >>> > > > >>> > > > >>> > > > >>> > > Thanks, > >>> > > > >>> > > > >>> > > Aniruddha > >>> > > > >>> > > On Thu, Jan 21, 2016 at 11:19 PM, Gaurav Gupta > >>> > > <[email protected]> > >>> > > wrote: > >>> > > > >>> > > > Aniruddha, > >>> > > > > >>> > > > Currently we don't have any support for that. > >>> > > > > >>> > > > Thanks > >>> > > > Gaurav > >>> > > > > >>> > > > Thanks > >>> > > > -Gaurav > >>> > > > > >>> > > > On Thu, Jan 21, 2016 at 12:24 AM, Tushar Gosavi > >>> > > > <[email protected]> > >>> > > > wrote: > >>> > > > > >>> > > > > Default FSStorageAgent can be used as it can work with local > >>> > > filesystem, > >>> > > > > but I far as I know there is no support for specifying the > >>> > > > > directory through xml file. by default it use the application > >>> > directory on HDFS. > >>> > > > > > >>> > > > > Not sure If we could specify storage agent with its properties > >>> > > > > through > >>> > > > the > >>> > > > > configuration at dag level. > >>> > > > > > >>> > > > > - Tushar. > >>> > > > > > >>> > > > > > >>> > > > > On Thu, Jan 21, 2016 at 12:14 PM, Aniruddha Thombare < > >>> > > > > [email protected]> wrote: > >>> > > > > > >>> > > > > > Hi, > >>> > > > > > > >>> > > > > > Do we have any storage agent which I can use readily, > >>> > > > > > configurable > >>> > > > > through > >>> > > > > > dt-site.xml? > >>> > > > > > > >>> > > > > > I am looking for something which would save checkpoints in > >>> > > > > > mounted > >>> > > file > >>> > > > > > system [eg. HA-NAS] which is basically just another directory > >>> > > > > > for > >>> > > Apex. > >>> > > > > > > >>> > > > > > > >>> > > > > > > >>> > > > > > > >>> > > > > > Thanks, > >>> > > > > > > >>> > > > > > > >>> > > > > > Aniruddha > >>> > > > > > > >>> > > > > > On Wed, Jan 20, 2016 at 8:33 PM, Sandesh Hegde < > >>> > > > [email protected]> > >>> > > > > > wrote: > >>> > > > > > > >>> > > > > > > It is already supported refer the following jira for more > >>> > > > information, > >>> > > > > > > > >>> > > > > > > https://issues.apache.org/jira/browse/APEXCORE-283 > >>> > > > > > > > >>> > > > > > > > >>> > > > > > > > >>> > > > > > > On Tue, Jan 19, 2016 at 10:43 PM Aniruddha Thombare < > >>> > > > > > > [email protected]> wrote: > >>> > > > > > > > >>> > > > > > > > Hi, > >>> > > > > > > > > >>> > > > > > > > Is it possible to save checkpoints in any other highly > >>> > > > > > > > available distributed file systems (which maybe mounted > >>> > > > > > > > directories across > >>> > > > the > >>> > > > > > > > cluster) other than HDFS? > >>> > > > > > > > If yes, is it configurable? > >>> > > > > > > > > >>> > > > > > > > AFAIK, there is no configurable option available to > achieve > >>> > that. > >>> > > > > > > > If that's the case, can we have that feature? > >>> > > > > > > > > >>> > > > > > > > This is with the intention to recover the applications > >>> > > > > > > > faster and > >>> > > > do > >>> > > > > > away > >>> > > > > > > > with HDFS's small files problem as described here: > >>> > > > > > > > > >>> > > > > > > > > >>> http://blog.cloudera.com/blog/2009/02/the-small-files-proble > >>> > > > > > > > m/ > >>> > > > > > > > > >>> > > > > > > > > >>> > > > > > > > >>> > > > > > > >>> > > > > > >>> > > > > >>> > > > >>> http://snowplowanalytics.com/blog/2013/05/30/dealing-with-hadoops-smal > >>> > > l-files-problem/ > >>> > > > > > > > > >>> > > > > >>> http://inquidia.com/news-and-info/working-small-files-hadoop-part-1 > >>> > > > > > > > > >>> > > > > > > > If we could save checkpoints in some other distributed > file > >>> > > system > >>> > > > > (or > >>> > > > > > > even > >>> > > > > > > > a HA NAS box) geared for small files, we could achieve - > >>> > > > > > > > > >>> > > > > > > > - Better performance of NN & HDFS for the production > >>> > > > > > > > usage > >>> > > > (read: > >>> > > > > > > > production data I/O & not temp files) > >>> > > > > > > > - Faster application recovery in case of planned > >>> shutdown > >>> > > > > > > > / > >>> > > > > > unplanned > >>> > > > > > > > restarts > >>> > > > > > > > > >>> > > > > > > > Please, send your comments, suggestions or ideas. > >>> > > > > > > > > >>> > > > > > > > Thanks, > >>> > > > > > > > > >>> > > > > > > > > >>> > > > > > > > Aniruddha > >>> > > > > > > > > >>> > > > > > > > >>> > > > > > > >>> > > > > > >>> > > > > >>> > > > >>> > > >>> > >> > >> > > >
