Thanks Mohammed.. This the Answer which i am looking for. Regards, Umang Shah
On Sat, Oct 18, 2014 at 5:11 AM, Mohammed Guller <moham...@glassbeam.com> wrote: > With 8GB RAM, the default heap size is 2GB, so you will quickly start > running out of heap space if you do large reads. What is a large read? It > depends on the number of columns in each row and data in each column. It > could 100,000 rows for some and 300,000 for others. In addition, remember > that Java adds a lot of overhead to data in memory, so a 8 character string > will not occupy just 8 bytes in memory, but a lot more. > > > > In general, avoid large reads in C*. If it is absolutely must and you > cannot repartition the data, then use a driver that supports paging. > > > > Mohammed > > > > *From:* Umang Shah [mailto:shahuma...@gmail.com] > *Sent:* Wednesday, October 15, 2014 10:46 PM > *To:* user@cassandra.apache.org > *Subject:* What will be system configuration for retrieving few "GB" of > data > > > > Hi, > > > > I am facing many problem after storing certain limit of records in > cassandra, and giving outofmemoryerror. > > > > I have 8GB of RAM in my system, so how much records i can expect to > retrieve by using select query? > > > > and what will be the configuration for those people who are retrieving > 15-20 GB of data? > > > > Can somebody explain me how to improve read performance then it will be > great help, i tried > > > http://www.datastax.com/documentation/cassandra/2.0/cassandra/operations/ops_tune_jvm_c.html > > > > such things but no help. > > > > > > -- > > Regards, > > Umang Shah > > shahuma...@gmail.com > -- Regards, Umang V.Shah +919886829019
