You should measure performance on the real-life cases and see if it's enough for you. Ignite performs good in both modes. If you really want to use ONHEAP_TIERED, you must tune GC and heap size, as described here [1] Make sure you have enough memory for your dataset. The goal is to avoid long GC pauses.
[1] https://apacheignite.readme.io/docs/jvm-and-system-tuning 2016-05-26 19:40 GMT+03:00 Tomek W <rrrtomtom...@gmail.com>: > Ok, I will try it. However, Why OFF_HEAP_TIERED ? It seem to be not fast > as ON HEAP > > 2016-05-26 18:32 GMT+02:00 Alexei Scherbakov <alexey.scherbak...@gmail.com > >: > >> We are talking about count(*) query performance, right ? >> WriteBehind is for writing to CacheStore in the async mode. >> >> If yes, do the following: >> >> 1) Set OFFHEAP_TIERED mode and reduce max heap memory on example to 4Gb. >> 2) Update to Ignite 1.6 >> 3) Measure query performance. Run the query several times and use average >> value as the estimation. >> 4) If it's not as expected, show me GC logs. >> >> >> >> 2016-05-26 18:28 GMT+03:00 Tomek W <rrrtomtom...@gmail.com>: >> >>> No, I am using ON_HEAP_TIERED. >>> >>> Maybe WriteBehind should be turned on ? >>> My App do exactly one thing: initialize hot loading. >>> >>> When it comes to JDBC client, I did show fragment of code in previous >>> post. >>> >>> 2016-05-26 16:15 GMT+02:00 Alexei Scherbakov < >>> alexey.scherbak...@gmail.com>: >>> >>>> I see long pauses in your GC log (> 3 seconds) >>>> This means your app have high pressure on the heap. >>>> It's hard to tell why without knowing what your app is doing. >>>> >>>> Are you using OFFHEAP_TIERED? >>>> If yes, try to reduce sqlOnheapRowCacheSize value. >>>> >>>> >>>> >>>> >>>> 2016-05-26 14:57 GMT+03:00 Tomek W <rrrtomtom...@gmail.com>: >>>> >>>>> Ok, >>>>> i am going to add new machines to ignite cluster. Firstly, please look >>>>> at my gc file log - previous message. >>>>> >>>>> 2016-05-26 13:39 GMT+02:00 Alexei Scherbakov < >>>>> alexey.scherbak...@gmail.com>: >>>>> >>>>>> Hi, >>>>>> >>>>>> The initial question was about setSqlOnheapRowCacheSize and I think >>>>>> now it is clear how to improve SQL performance using with parameter. >>>>>> >>>>>> If you dissatisfied with the Ignite performance, I suggest you to >>>>>> start a new thread on this, >>>>>> providing detailed info about your performance test like >>>>>> cluster configuration, server GC settings, and test sources. >>>>>> >>>>>> As already mentioned, Ignite SQL engine(H2) has the same(or slightly) >>>>>> less performance when Postresql. >>>>>> Ignite really starts to shine when used as distributed data grid >>>>>> having large amount of data in memory on several nodes. >>>>>> >>>>>> SELECT count(*) from table is not very good test query. >>>>>> Postgres may have the result cached, whereas Ignite always do the >>>>>> full table traversal. >>>>>> Recently I implemented an improvement for this case. >>>>>> See https://issues.apache.org/jira/browse/IGNITE-2751 for details. >>>>>> >>>>>> I strongly recommend to test Ignite performance on the real case. >>>>>> Dont' forget to configure GC properly [1] >>>>>> >>>>>> [1] https://apacheignite.readme.io/docs/jvm-and-system-tuning >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> 2016-05-26 2:09 GMT+03:00 Tomek W <rrrtomtom...@gmail.com>: >>>>>> >>>>>>> | Also it would be interesting to see result of >>>>>>> | SELECT count(*) from the query above in both cases. >>>>>>> (number of rows = 2 798 685) >>>>>>> SELECT count(*) FROM postgresTable; >>>>>>> 456 ms >>>>>>> SELECT count(*) FROM postgresTable; >>>>>>> 314 ms >>>>>>> >>>>>>> SELECT count(*) FROM igniteTable; >>>>>>> 9746 ms >>>>>>> SELECT count(*) FROM igniteTable; >>>>>>> 9664 ms >>>>>>> >>>>>>> >>>>>>> Code of Jdbc Drvier (the same code for Ignite and postgresql - url >>>>>>> connection is given from command line): >>>>>>> http://pastebin.com/mYDSjziN >>>>>>> My start sh file: >>>>>>> http://pastebin.com/VmRM2sPQ >>>>>>> >>>>>>> My gc log file (following hint Magda): >>>>>>> (file generated during hot loading and query via JDBC). >>>>>>> http://pastebin.com/XicnNczV >>>>>>> >>>>>>> >>>>>>> If you would like to see something else let me know. >>>>>>> >>>>>>> PS How to launch H2 debug console ? I followed docs, but it doesn't >>>>>>> help. >>>>>>> I set enviroment variable: >>>>>>> echo $IGNITE_H2_DEBUG_CONSOLE >>>>>>> true >>>>>>> now, ./ignite.sh conf.xml >>>>>>> >>>>>>> sudo netstat -tulpn | grep 61214 >>>>>>> No opened ports. >>>>>>> >>>>>>> BTW, during starting ignite it give me information: >>>>>>> [01:03:02] Performance suggestions for grid >>>>>>> 'turbines_table_cluster' (fix if possible) >>>>>>> [01:03:02] To disable, set >>>>>>> -DIGNITE_PERFORMANCE_SUGGESTIONS_DISABLED=true >>>>>>> [01:03:02] ^-- Disable grid events (remove 'includeEventTypes' >>>>>>> from configuration) >>>>>>> [01:03:02] ^-- Enable ATOMIC mode if not using transactions (set >>>>>>> 'atomicityMode' to ATOMIC) >>>>>>> [01:03:02] ^-- Enable write-behind to persistent store (set >>>>>>> 'writeBehindEnabled' to true) >>>>>>> >>>>>>> >>>>>>> 2016-05-25 12:23 GMT+02:00 Alexei Scherbakov < >>>>>>> alexey.scherbak...@gmail.com>: >>>>>>> >>>>>>>> For postgres test I mean initial jdbc query and result >>>>>>>> set traversal. >>>>>>>> For Ignite I mean sql query and iterator traversal. >>>>>>>> Also it would be interesting to see result of >>>>>>>> *SELECT count(*) from the query above in both cases.* >>>>>>>> >>>>>>>> 2016-05-25 12:00 GMT+03:00 Tomek W <rrrtomtom...@gmail.com>: >>>>>>>> >>>>>>>>> [image: Obraz w treści 1] >>>>>>>>> >>>>>>>>> What code do you mean ? JDBC client ? >>>>>>>>> >>>>>>>>> 2016-05-25 10:25 GMT+02:00 Alexei Scherbakov < >>>>>>>>> alexey.scherbak...@gmail.com>: >>>>>>>>> >>>>>>>>>> What's the batch size for postgresql ? >>>>>>>>>> What's the size of one entry ? >>>>>>>>>> Could you provide the test code for both postgres and Ignite >>>>>>>>>> (just the query + read with the time estimation) ? >>>>>>>>>> >>>>>>>>>> 2016-05-25 11:13 GMT+03:00 Tomek W <rrrtomtom...@gmail.com>: >>>>>>>>>> >>>>>>>>>>> | How many entries are downloaded to the client in both cases? >>>>>>>>>>> 3000 000 >>>>>>>>>>> >>>>>>>>>>> | Do the both queries involve network I/O ? >>>>>>>>>>> No, I have only local one server (for testing purpose). >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> 2016-05-25 9:59 GMT+02:00 Alexei Scherbakov < >>>>>>>>>>> alexey.scherbak...@gmail.com>: >>>>>>>>>>> >>>>>>>>>>>> SELECT * is not really a good test query. >>>>>>>>>>>> It's result can be affected not only by engine performance. >>>>>>>>>>>> >>>>>>>>>>>> How many entries are downloaded to the client in both cases? >>>>>>>>>>>> Do the both queries involve network I/O ? >>>>>>>>>>>> >>>>>>>>>>>> 2016-05-25 7:58 GMT+03:00 Denis Magda <dma...@gridgain.com>: >>>>>>>>>>>> >>>>>>>>>>>>> In general Ignite is designed to be used in a distributed >>>>>>>>>>>>> environment when gigabytes or terabytes of dataset is spread >>>>>>>>>>>>> across many >>>>>>>>>>>>> cluster nodes and SQL queries executed across the cluster should >>>>>>>>>>>>> be faster >>>>>>>>>>>>> since resources of all the machines will be used and as a result >>>>>>>>>>>>> a query >>>>>>>>>>>>> should be completed quicker. In your scenario you just have only >>>>>>>>>>>>> a single >>>>>>>>>>>>> cluster node and in fact comparing performance of PostgreSQL and >>>>>>>>>>>>> H2 (engine >>>>>>>>>>>>> that is used by Ignite SQL) and I can consider that Ignite SQL >>>>>>>>>>>>> can work >>>>>>>>>>>>> slightly slowly but this in is not Ignite usage scenario. >>>>>>>>>>>>> >>>>>>>>>>>>> However if you try to create a cluster of several nodes >>>>>>>>>>>>> running on different physical machines, pre-load gigabytes of >>>>>>>>>>>>> data there >>>>>>>>>>>>> and compare Ignite SQL and PostgresSQL you should see performance >>>>>>>>>>>>> improvements on Ignite side. >>>>>>>>>>>>> >>>>>>>>>>>>> In any case taking into account the advise above do the >>>>>>>>>>>>> following: >>>>>>>>>>>>> - execute “EXPLAIN” query to see that the index is chose >>>>>>>>>>>>> properly [1]; >>>>>>>>>>>>> - H2 console will allow you to see how fast a query is >>>>>>>>>>>>> presently executed on a single node removing several Ignite >>>>>>>>>>>>> layers [2]; >>>>>>>>>>>>> - check if you have any GC pauses during query execution since >>>>>>>>>>>>> it can affect execution time [3] >>>>>>>>>>>>> >>>>>>>>>>>>> Also share the objects you use as keys and values. >>>>>>>>>>>>> >>>>>>>>>>>>> [1] >>>>>>>>>>>>> https://apacheignite.readme.io/docs/sql-queries#using-explain >>>>>>>>>>>>> [2] >>>>>>>>>>>>> https://apacheignite.readme.io/docs/sql-queries#using-h2-debug-console >>>>>>>>>>>>> [3] >>>>>>>>>>>>> https://apacheignite.readme.io/v1.6/docs/jvm-and-system-tuning#section-detailed-garbage-collection-stats >>>>>>>>>>>>> >>>>>>>>>>>>> — >>>>>>>>>>>>> Denis >>>>>>>>>>>>> >>>>>>>>>>>>> On May 25, 2016, at 3:23 AM, Tomek W <rrrtomtom...@gmail.com> >>>>>>>>>>>>> wrote: >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> +==============================================================================================+ >>>>>>>>>>>>> | Node ID8(@), IP | CPUs | Heap Used | CPU Load | >>>>>>>>>>>>> Up Time | Size | Hi/Mi/Rd/Wr | >>>>>>>>>>>>> >>>>>>>>>>>>> +==============================================================================================+ >>>>>>>>>>>>> | 0F0AAF99(@n0), 127.0.0.1 | 8 | 54.50 % | 3.23 % | >>>>>>>>>>>>> 00:13:13:49 | 3000000 | Hi: 0 | >>>>>>>>>>>>> | | | | >>>>>>>>>>>>> | | | Mi: 0 | >>>>>>>>>>>>> | | | | >>>>>>>>>>>>> | | | Rd: 0 | >>>>>>>>>>>>> | | | | >>>>>>>>>>>>> | | | Wr: 0 | >>>>>>>>>>>>> >>>>>>>>>>>>> +----------------------------------------------------------------------------------------------+ >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> I followed your hints. Actually, client doesn't require such >>>>>>>>>>>>> many memory as before - thanks for it. >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> When it comes to configuration of server, I also followed your >>>>>>>>>>>>> hints, results: >>>>>>>>>>>>> >>>>>>>>>>>>> Querying is done by JDBC Client. In ignite and postgresql I >>>>>>>>>>>>> have single index on column A. >>>>>>>>>>>>> >>>>>>>>>>>>> Ignite: SELECT * FROM table WHERE A > 1345 takes 6s. >>>>>>>>>>>>> Postgres: SELECT * FROM table WHERE A > 1345 takes 4s. >>>>>>>>>>>>> >>>>>>>>>>>>> As you can see, postgres is still bettter than Ignite. I >>>>>>>>>>>>> show you significant fragments of my configuration: >>>>>>>>>>>>> http://pastebin.com/EQC4JPWR >>>>>>>>>>>>> >>>>>>>>>>>>> And xml for server file: >>>>>>>>>>>>> http://pastebin.com/enR9h5J4 >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> Try to consider why postgresql is still better, please. >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> -- >>>>>>>>>>>> >>>>>>>>>>>> Best regards, >>>>>>>>>>>> Alexei Scherbakov >>>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> -- >>>>>>>>>> >>>>>>>>>> Best regards, >>>>>>>>>> Alexei Scherbakov >>>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> -- >>>>>>>> >>>>>>>> Best regards, >>>>>>>> Alexei Scherbakov >>>>>>>> >>>>>>> >>>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> >>>>>> Best regards, >>>>>> Alexei Scherbakov >>>>>> >>>>> >>>>> >>>> >>>> >>>> -- >>>> >>>> Best regards, >>>> Alexei Scherbakov >>>> >>> >>> >> >> >> -- >> >> Best regards, >> Alexei Scherbakov >> > > -- Best regards, Alexei Scherbakov
