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Honghai Chen commented on KAFKA-1646: ------------------------------------- Actually we want to add one more column to file "recovery-point-offset-checkpoint", currently it only record offset, like below: 0 2 mvlogs 1 100 mvlogs 0 200 Change to below: 0 2 mvlogs 1 100 8000 mvlogs 0 200 16000 8000 is the start position of the data file for message with offset 100 . And 16000 is start position of the data file for message with offset 200. Take first one as example, when recover the last segment (in function LogSegment.recover(maxMessageSize: Int) , ONLY recover file to min(validBytes, 8000) with offset 100 and rebuild index. Make sense ? [~jkreps] > Improve consumer read performance for Windows > --------------------------------------------- > > Key: KAFKA-1646 > URL: https://issues.apache.org/jira/browse/KAFKA-1646 > Project: Kafka > Issue Type: Improvement > Components: log > Affects Versions: 0.8.1.1 > Environment: Windows > Reporter: xueqiang wang > Assignee: xueqiang wang > Labels: newbie, patch > Attachments: Improve consumer read performance for Windows.patch, > KAFKA-1646-truncate-off-trailing-zeros-on-broker-restart-if-bro.patch, > KAFKA-1646_20141216_163008.patch > > > This patch is for Window platform only. In Windows platform, if there are > more than one replicas writing to disk, the segment log files will not be > consistent in disk and then consumer reading performance will be dropped down > greatly. This fix allocates more disk spaces when rolling a new segment, and > then it will improve the consumer reading performance in NTFS file system. > This patch doesn't affect file allocation of other filesystems, for it only > adds statements like 'if(Os.iswindow)' or adds methods used on Windows. -- This message was sent by Atlassian JIRA (v6.3.4#6332)