Hi Sorry I was not able to access your chart of put perf. Is it like the performance gradually coming down and at some point again getting better all of a sudden? [some spikes in graph] It may be because of HBASE-3484
You can check the memstore size that u have given and see whether the spikes coming at the memstore flush time and then again perf going down gradually... -Anoop- __________ From: Giorgi Jvaridze [[email protected]] Sent: Monday, June 18, 2012 7:28 PM To: [email protected] Subject: Decreasing write speed over time Hello list, I have Hbase (CDH4) setup of a master and 4 region servers (8 core 2.0GHz, 6GB of RAM and 6 100GB disks per data node). All of them are virtual machines. I'm writing into a table using single thread w/ auto flush off. Ids are increased by one and then reversed. Data is a string with average length 150 chars. I'm measuring time needed for writing one million rows. At first I got quite good results, it could write about 40-50K rows in a second but after time this speed decreased. I have a chart showing how It has been decreased by the time and data got bigger. At the end of chart it's about 2 billion rows inserted. http://i.minus.com/iRFtEoVJVsFso.png Is this expected behavior for this kind of setup or something could went wrong and I should check it up? Thanks! Giorgi
