Prashanth, "will it will it spread out the stop-the-world time across the intervals. In that case, my average would fall to same figures right?
It's hard to say - you'd have to give it a try and see if it improves. There are a lot of different optimizations, both at the JVM and the Operating System level, that come into play here. It may give much better performance. Or perhaps worse performance, but it's certainly worth trying out. Thanks -Mark On Jun 13, 2018, at 1:04 PM, V, Prashanth (Nokia - IN/Bangalore) <prashant...@nokia.com<mailto:prashant...@nokia.com>> wrote: Mark, Thanks for the reply. Please find the comments inline. Thanks & Regards, Prashanth From: Mark Payne [mailto:marka...@hotmail.com] Sent: Wednesday, June 13, 2018 6:07 PM To: users@nifi.apache.org<mailto:users@nifi.apache.org> Subject: Re: NiFi Performance Analysis Clarification Prashanth, Whenever the FlowFile Repository performs a Checkpoint, it has to ensure that it has flushed all data to disk before continuing, so it performs an fsync() call so that any data buffered by the Operating System is flushed to disk as well. If you're using the same physical drive / physical partition for FlowFile Repository as you are for content, provenance, logs, etc. then this can be very costly. It is always a best practice for any production system to try to isolate the FlowFile Repository to its own physical partition, the Content Repository to its own physical partition (or multiple partitions) and the Provenance Repository to its own physical partition (or multiple partitions). Placing the FlowFile Repo on its own partition is likely to address the issue on its own (Update the value of the "nifi.flowfile.repository.directory" property in nifi.properties - but be warned, you'll lose any data in your flow if you point to an empty directory so you'll need to also move the contents of ./flowfile_repository to the new directory or stop your source processors and bleed out all the data from your flow first). I tried once by giving flowfile repo in one partition and content& provenance in other. But I think still I faced this problem. But didn’t remember well. Additionally, you may see better results by adjusting the value of the "nifi.flowfile.repository.checkpoint.interval" property from "2 mins" to something smaller like "15 secs". Oh thats nice. I will try this config. But , just curious, will it spread out the stop-the-world time across the intervals. In that case, my average would fall to same figures right? Thanks -Mark On Jun 13, 2018, at 8:10 AM, V, Prashanth (Nokia - IN/Bangalore) <prashant...@nokia.com<mailto:prashant...@nokia.com>> wrote: Hi Mike, Thanks for the reply. Actually , we did all those optimisations with kafka. I am converting to avro, also I configured kafka producer properties accordingly. I believe kafka is not a bottleneck. I am sure because, I can see pretty good throughput with my flow. But average throughput is reduced as stop-the-world signal happening for long time. Correct me if I am wrong.. Thanks & Regards, Prashanth From: Mike Thomsen [mailto:mikerthom...@gmail.com] Sent: Wednesday, June 13, 2018 4:23 PM To: V, Prashanth (Nokia - IN/Bangalore) <prashant...@nokia.com<mailto:prashant...@nokia.com>> Cc: users@nifi.apache.org<mailto:users@nifi.apache.org>; pierre.villard...@gmail.com<mailto:pierre.villard...@gmail.com> Subject: Re: NiFi Performance Analysis Clarification Relevant: http://www.idata.co.il/2016/09/moving-binary-data-with-kafka/ If you're throwing 1MB and bigger files at Kafka, that's probably where your slowdown is occurring. Particularly if you're running a single node or just two nodes. Kafka was designed to process extremely high volumes of small messages (at most 10s of kb, not MB and certainly not GB). What you can try is building an Avro schema for your CSV files and using PublishKafkaRecord to break everything down into records that are an appropriate fit for Kafka. On Wed, Jun 13, 2018 at 6:38 AM V, Prashanth (Nokia - IN/Bangalore) <prashant...@nokia.com<mailto:prashant...@nokia.com>> wrote: Please find answers inline Thanks & Regards, Prashanth From: Pierre Villard [mailto:pierre.villard...@gmail.com<mailto:pierre.villard...@gmail.com>] Sent: Wednesday, June 13, 2018 3:56 PM To: users@nifi.apache.org<mailto:users@nifi.apache.org> Subject: Re: NiFi Performance Analysis Clarification Hi, What's the version of NiFi you're using? 1.6.0 What are the file systems you're using for the repositories? Local rhel file system (/home dir) I think that changing the heap won't make any different in this case. I'd keep it to something like 8GB (unless you're doing very specific stuff that are memory consuming) and let the remaining to OS and disk caching. I think NiFi holds the snapshotmap in memory.. since we are dealing with pretty huge ingress data [I allocated 32GB out of 42GB to NiFi]. Hence, I increased so. Does this has anything to do with flowfile checkpoint delay? Pierre 2018-06-13 11:58 GMT+02:00 V, Prashanth (Nokia - IN/Bangalore) <prashant...@nokia.com<mailto:prashant...@nokia.com>>: Hi Mike, I am retrieving many small csv files each of size 1MB (total folder size around ~100GB). In update step, I am doing some enrichment on ingress csv. Anyway my flow doesn’t do anything with the stop the world time right? Can you please tell me about flowfile checkpointing related tunings? Thanks & Regards, Prashanth From: Mike Thomsen [mailto:mikerthom...@gmail.com<mailto:mikerthom...@gmail.com>] Sent: Wednesday, June 13, 2018 2:33 PM To: users@nifi.apache.org<mailto:users@nifi.apache.org> Subject: Re: NiFi Performance Analysis Clarification What are you retrieving (particularly size) and what happens in the "update" step? Thanks, Mike On Wed, Jun 13, 2018 at 4:10 AM V, Prashanth (Nokia - IN/Bangalore) <prashant...@nokia.com<mailto:prashant...@nokia.com>> wrote: Hi Team, I am doing some performance testing in NiFi. WorkFlow is GetSFTP -> update -> PutKafka. I want to tune my setup to achieve high throughput without much queuing. But my throughput average drops during flowfile checkpointing duration. I believe stop-the-world is happening during that time. I can roughly read ~100MB/s from SFTP and send almost same to Kafka. But every 2 mins, it stops the complete execution. Check below logs 2018-06-13 13:24:21,160 INFO [pool-10-thread-1] o.a.n.c.r.WriteAheadFlowFileRepository Initiating checkpoint of FlowFile Repository 2018-06-13 13:24:49,420 INFO [Write-Ahead Local State Provider Maintenance] org.wali.MinimalLockingWriteAheadLog org.wali.MinimalLockingWriteAheadLog@cf82c58<mailto:org.wali.MinimalLockingWriteAheadLog@cf82c58> checkpointed with 23 Records and 0 Swap Files in 39353 milliseconds (Stop-the-world time = 3 milliseconds, Clear Edit Logs time = 3 millis), max Transaction ID 68 2018-06-13 13:25:00,165 INFO [pool-10-thread-1] o.a.n.wali.SequentialAccessWriteAheadLog Checkpointed Write-Ahead Log with 7 Records and 0 Swap Files in 39002 milliseconds (Stop-the-world time = 28275 milliseconds), max Transaction ID 316705 2018-06-13 13:25:00,169 INFO [pool-10-thread-1] o.a.n.c.r.WriteAheadFlowFileRepository Successfully checkpointed FlowFile Repository with 7 records in 39008 milliseconds I think all processor goes in idle state for 39 seconds ☹ .. Please guide how to tune it.. I changed the heap memory with 32G [I am testing on 12 core, 48G machine]. I disabled content-repository archiving. All other properties remains same. Thanks & Regards, Prashanth
