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Babulal commented on CARBONDATA-1281: ------------------------------------- Hi Can you please try option carbon.tempstore.locations In carbon.properties . It will accept mutiple disks to local store/sort. Thanks Babu > Disk hotspot found during data loading > -------------------------------------- > > Key: CARBONDATA-1281 > URL: https://issues.apache.org/jira/browse/CARBONDATA-1281 > Project: CarbonData > Issue Type: Improvement > Components: core, data-load > Affects Versions: 1.1.0 > Reporter: xuchuanyin > Time Spent: 1h > Remaining Estimate: 0h > > # Scenario > Currently we have done a massive data loading. The input data is about 71GB > in CSV format,and have about 88million records. When using carbondata, we do > not use any dictionary encoding. Our testing environment has three nodes and > each of them have 11 disks as yarn executor directory. We submit the loading > command through JDBCServer.The JDBCServer instance have three executors in > total, one on each node respectively. The loading takes about 10minutes > (+-3min vary from each time). > We have observed the nmon information during the loading and find: > 1. lots of CPU waits in the first half of loading; > 2. only one single disk has many writes and almost reaches its bottleneck > (Avg. 80M/s, Max. 150M/s on SAS Disk) > 3. the other disks are quite idel > # Analyze > When do data loading, carbondata read and sort data locally(default scope) > and write the temp files to local disk. In my case, there is only one > executor in one node, so carbondata write all the temp file to one > disk(container directory or yarn local directory), thus resulting into single > disk hotspot. > # Modification > We should support multiple directory for writing temp files to avoid disk > hotspot. > Ps: I have improved this in my environment and the result is pretty > optimistic: the loading takes about 6minutes (10 minutes before improving). -- This message was sent by Atlassian JIRA (v6.4.14#64029)