Thanks a lot Steve. I suspected the same. I will definitely read. regards Neha
On Fri, Jan 23, 2015 at 11:22 PM, Steve Robenalt <sroben...@highwire.org> wrote: > Hi Neha, > > As far as I'm aware, 4GB of RAM is a bit underpowered for Cassandra even > if there are no other processes on the same server (i.e. Tomcat and > ActiveMQ). There are some general guidelines at > http://wiki.apache.org/cassandra/CassandraHardware which should help you > out. You may not need all of the recommendations therein if you are simply > evaluating Cassandra with a test workload, but I suspect you will at least > need more RAM and a dedicated machine to get beyond the read timeouts. > Also, when using spinning disks, the 2 drive recommendation is important > because Cassandra uses two very different access patterns for its data > storage and the disk can be thrashed quite a bit, particularly if you end > up using enough memory that virtual memory on the host becomes a factor. > > There's a lot of good information on both the Apache Cassandra site and on > Planet Cassandra about performance and tuning if you want to know more. > > Hope that helps, > Steve > > > > > On Thu, Jan 22, 2015 at 7:28 PM, Neha Trivedi <nehajtriv...@gmail.com> > wrote: > >> Hello Everyone, >> Thanks very much for the input. >> >> Here is my System info. >> 1. I have single node cluster. (For testing) >> 2. I have 4GB Memory on the Server and trying to process 200B. ( 1GB is >> allocated to Tomcat7, 1 GB to Cassandra and 1 GB to ActiveMQ. Also nltk >> Server is running) >> 3. We are using 2.03 Driver (This is one I can change and try) >> 4. 64.4 GB HDD >> 5. Attached Memory and CPU information. >> >> Regards >> Neha >> >> On Fri, Jan 23, 2015 at 6:50 AM, Steve Robenalt <sroben...@highwire.org> >> wrote: >> >>> I agree with Rob. You shouldn't need to change the read timeout. >>> >>> We had similar issues with intermittent ReadTimeoutExceptions for a >>> while when we ran Cassandra on underpowered nodes on AWS. We've also seen >>> them when executing unconstrained queries with very large ResultSets >>> (because it takes longer than the timeout to return results). If you can >>> share more details about the hardware environment you are running your >>> cluster on, there are many on the list who can tell you if they are >>> underpowered or not (CPUs, memory, and disk/storage config are all >>> important factors). >>> >>> You might also try running a newer version of the Java Driver (the later >>> 2.0.x drivers should all work with Cassandra 2.0.3), and I would also >>> suggest moving to a newer (2.0.x) version of Cassandra if you have the >>> option to do so. We had to move to Cassandra 2.0.5 some time ago from 2.0.3 >>> for an issue unrelated to the read timeouts. >>> >>> Steve >>> >>> >>> On Thu, Jan 22, 2015 at 4:48 PM, Robert Coli <rc...@eventbrite.com> >>> wrote: >>> >>>> On Thu, Jan 22, 2015 at 4:19 PM, Asit KAUSHIK < >>>> asitkaushikno...@gmail.com> wrote: >>>> >>>>> There are some values for read timeout in Cassandra.yaml file and the >>>>> default value is 30000 ms change to a bigger value and that resolved our >>>>> issue. >>>>> >>>> Having to increase this value is often a strong signal you are Doing It >>>> Wrong. FWIW! >>>> >>>> =Rob >>>> >>>> >>> >>> >> >
