Jim, It is very possible/likely that correcting the number of file handles linux allows a process to have will get nifi back on track.
Thanks Joe On Tue, Mar 28, 2017 at 8:13 AM, James McMahon <[email protected]> wrote: > No apology necessary Aldrin. I'm much obliged to you and to Joe for all your > help. My game plan is as follows: > 1- speak with the admin of my Linux box about executing all the sys admin > "best practice" changes > 2- barring doing them all, at minimum increase max permitted open files from > 1024 to 50000 > 3- reboot my Linux box, and then attempt to start NiFi > 4- if 3 fails, rm -rf ./flowfile_repository on this, my dev box. Start nifi, > get in there, and eliminate that Python logging. Find another way to log > results to a system file, perhaps using a NiFi processor. > > - Jim > > On Tue, Mar 28, 2017 at 7:54 AM, Aldrin Piri <[email protected]> wrote: >> >> Hi Jim, >> >> Apologies for terse response earlier, was typing from phone. >> >> I am assuming you are on a Linux system. >> >> First and foremost, do checkout the Sys Admin guide [1]. In particular, >> scope out the best practices [2] for configuration which will have you >> increase your open file handles. >> >> I do suspect that your hunches are correct, and while this will aid and >> maybe avoid the issue, getting those resources properly closed out will be >> the right thing to track down. >> >> Regardless of state, production or dev, there are certainly ways to manage >> this a bit more and work files through in an iterative manner. >> >> Please report back if these avenues don't solve your issues and we can >> dive a little deeper if needed. >> >> [1] https://nifi.apache.org/docs/nifi-docs/html/administration-guide.html >> [2] >> https://nifi.apache.org/docs/nifi-docs/html/administration-guide.html#configuration-best-practices >> >> On Tue, Mar 28, 2017 at 7:46 AM, James McMahon <[email protected]> >> wrote: >>> >>> Hi Aldrin. Yes sir, of course: my environment is NiFi v0.7. I have my >>> content, flowfile, and provenance repositories on separate independent disk >>> devices. In my nifi.properties file, nifi.flowfile.repository.partitions >>> equals 256, and always.sync is false. My nifi.queue.swap.threshold is 20000. >>> Since I am currently in development and so this is not a production process, >>> I have set nifi.flowcontroller.autoResumeState to false. In >>> conf/bootstrap.conf, my JVM memory settings are -Xms1024m and -Xmx4096m. >>> >>> In fact I have not yet applied the best practices from the Sys Admin >>> Guide. I will speak with them about doing this today. I am a little hesitant >>> to just jump into making the seven system changes you detail. NiFi does run >>> on this box, but so do other processed that may be impacted. what's good for >>> NiFi may not be good for these other processes, and so I want to ask first. >>> >>> My scripts employ a Python stream callback to grab values from select >>> attributes, populate those into a Python dictionary object, generate a json >>> object from that dictionary object, and replace the flowfile contents with >>> that dictionary object. These scripts are called by ExecuteScript >>> processors. Similar scripts are used at various points throughout my >>> workflow, near the end of each branch. Those had been working without any >>> problems until I tried to introduce Python logging yesterday. I suspect I am >>> not releasing file handler resources and logger objects as flowfiles flow >>> through these ExecuteScript processors - maybe? I really am only making >>> educated guesses at this stage. My first objective today is to get NiFi to >>> come back up. >>> >>> Please tell me: while I am in a dev state right now, had I been in a >>> production state what would have been the repercussions of deleting in its >>> entirety the flowfile_repository, which includes all its journal files? >>> >>> Thanks very much in advance for your help. >>> >>> Jim >>> >>> On Tue, Mar 28, 2017 at 6:57 AM, Aldrin Piri <[email protected]> >>> wrote: >>>> >>>> Hi Jim, >>>> >>>> In getting to the root cause, could you please provide information on >>>> your environment? Did you apply the best practices listed in the System >>>> Administrator's guide? Could you provide some details on what your scripts >>>> are doing? >>>> >>>> If the data is not of importance, removing the Flowfile Repo should get >>>> you going. You can additionally remove the content repo, but this should be >>>> cleaned up by the framework as no flowfiles will point to said content. >>>> >>>> >>>> Aldrin Piri >>>> Sent from my mobile device. >>>> >>>> On Mar 28, 2017, at 06:12, James McMahon <[email protected]> wrote: >>>> >>>> I noticed, too, that I have many partitions, partition-0 to >>>> partition-255 to be exact. These all have journal files in them. So I >>>> suspect that the journal file I cited is not specifically the problem in >>>> and >>>> of itself, but instead is the point where the allowable open files >>>> threshold >>>> is reached. I'm wondering if I have to recover by deleting all these >>>> partitions? -Jim >>>> >>>> On Tue, Mar 28, 2017 at 5:58 AM, James McMahon <[email protected]> >>>> wrote: >>>>> >>>>> While trying to use Python logging from two scripts I call via two >>>>> independent ExecuteScript processors, I seem to have inadvertently >>>>> created a >>>>> condition where I have too many files open. This is causing a serious >>>>> challenge for me, because when I attempt to start nifi (v0.7.1) it fails. >>>>> >>>>> The log indicates that the flow controller cannot be started, and it >>>>> cites the cause as this: >>>>> org.apache.nifi.web.NiFiCoreException: Unable to start Flow Controller >>>>> . >>>>> . (many stack trace entries) >>>>> . >>>>> Caused by: java.nio.file.FileSystemException: >>>>> /mnt/flow_repo/flowfile_repository/partition-86/83856.journal: Too many >>>>> files open >>>>> >>>>> In a situation like this, what is the best practice for recovery? Is it >>>>> permissible to simply delete this journal file? What are the negative >>>>> repercussions of doing that? >>>>> >>>>> I did already try deleting my provenance_repository, but that did not >>>>> allow nifi to restart. (NiFi did re-establish my provenance_repository at >>>>> restart). >>>>> >>>>> Thanks very much in advance for your help. -Jim >>>> >>>> >>> >> >
