Re: Any experience of 20 node mini-itx cassandra cluster
I already have thanks. I'll do the tests with the hardware arrives. Thanks Jabbar Azam On 16 April 2013 22:27, aaron morton aa...@thelastpickle.com wrote: Can't we use LCS? Do some reading and some tests… http://www.datastax.com/dev/blog/leveled-compaction-in-apache-cassandra http://www.datastax.com/dev/blog/when-to-use-leveled-compaction Cheers - Aaron Morton Freelance Cassandra Consultant New Zealand @aaronmorton http://www.thelastpickle.com On 15/04/2013, at 10:44 PM, Jabbar Azam aja...@gmail.com wrote: I know the SSD's are a bit small but they should be enough for our application. Out test data is 1.6 TB(including replication of rf=3). Can't we use LCS? This will give us more space at the expensive of more I/O but SSD's have loads of I/Os. Thanks Jabbar Azam On 14 April 2013 20:20, Jabbar Azam aja...@gmail.com wrote: Thanks Aaron. Thanks Jabbar Azam On 14 April 2013 19:39, aaron morton aa...@thelastpickle.com wrote: That's better. The SSD size is a bit small, and be warned that you will want to leave 50Gb to 100GB free to allow room for compaction (using the default size tiered). On the ram side you will want to run about 4GB (assuming cass 1.2) for the JVM the rest can be off heap Cassandra structures. This may not leave too much free space for the os page cache, but SSD may help there. Cheers - Aaron Morton Freelance Cassandra Consultant New Zealand @aaronmorton http://www.thelastpickle.com On 13/04/2013, at 4:47 PM, Jabbar Azam aja...@gmail.com wrote: What about using quad core athlon x4 740 3.2 GHz with 8gb of ram and 256gb ssds? I know it will depend on our workload but will be better than a dual core CPU. I think Jabbar Azam On 13 Apr 2013 01:05, Edward Capriolo edlinuxg...@gmail.com wrote: Duel core not the greatest you might run into GC issues before you run out of IO from your ssd devices. Also cassandra has other concurrency settings that are tuned roughly around the number of processors/cores. It is not uncommon to see 4-6 cores of cpu (600 % in top dealing with young gen garbage managing lots of sockets whatever. On Fri, Apr 12, 2013 at 12:02 PM, Jabbar Azam aja...@gmail.com wrote: That's my guess. My colleague is still looking at CPU's so I'm hoping he can get quad core CPU's for the servers. Thanks Jabbar Azam On 12 April 2013 16:48, Colin Blower cblo...@barracuda.com wrote: If you have not seen it already, checkout the Netflix blog post on their performance testing of AWS SSD instances. http://techblog.netflix.com/2012/07/benchmarking-high-performance-io-with.html My guess, based on very little experience, is that you will be CPU bound. On 04/12/2013 03:05 AM, Jabbar Azam wrote: Hello, I'm going to be building a 20 node cassandra cluster in one datacentre. The spec of the servers will roughly be dual core Celeron CPU, 256 GB SSD, 16GB RAM and two nics. Has anybody done any performance testing with this setup or have any gotcha's I should be aware of wrt to the hardware? I do realise the CPU is fairly low computational power but I'm going to assume the system is going to be IO bound hence the RAM and SSD's. Thanks Jabbar Azam -- *Colin Blower* *Software Engineer* Barracuda Networks Inc. +1 408-342-5576 (o)
Re: Any experience of 20 node mini-itx cassandra cluster
I know the SSD's are a bit small but they should be enough for our application. Out test data is 1.6 TB(including replication of rf=3). Can't we use LCS? This will give us more space at the expensive of more I/O but SSD's have loads of I/Os. Thanks Jabbar Azam On 14 April 2013 20:20, Jabbar Azam aja...@gmail.com wrote: Thanks Aaron. Thanks Jabbar Azam On 14 April 2013 19:39, aaron morton aa...@thelastpickle.com wrote: That's better. The SSD size is a bit small, and be warned that you will want to leave 50Gb to 100GB free to allow room for compaction (using the default size tiered). On the ram side you will want to run about 4GB (assuming cass 1.2) for the JVM the rest can be off heap Cassandra structures. This may not leave too much free space for the os page cache, but SSD may help there. Cheers - Aaron Morton Freelance Cassandra Consultant New Zealand @aaronmorton http://www.thelastpickle.com On 13/04/2013, at 4:47 PM, Jabbar Azam aja...@gmail.com wrote: What about using quad core athlon x4 740 3.2 GHz with 8gb of ram and 256gb ssds? I know it will depend on our workload but will be better than a dual core CPU. I think Jabbar Azam On 13 Apr 2013 01:05, Edward Capriolo edlinuxg...@gmail.com wrote: Duel core not the greatest you might run into GC issues before you run out of IO from your ssd devices. Also cassandra has other concurrency settings that are tuned roughly around the number of processors/cores. It is not uncommon to see 4-6 cores of cpu (600 % in top dealing with young gen garbage managing lots of sockets whatever. On Fri, Apr 12, 2013 at 12:02 PM, Jabbar Azam aja...@gmail.com wrote: That's my guess. My colleague is still looking at CPU's so I'm hoping he can get quad core CPU's for the servers. Thanks Jabbar Azam On 12 April 2013 16:48, Colin Blower cblo...@barracuda.com wrote: If you have not seen it already, checkout the Netflix blog post on their performance testing of AWS SSD instances. http://techblog.netflix.com/2012/07/benchmarking-high-performance-io-with.html My guess, based on very little experience, is that you will be CPU bound. On 04/12/2013 03:05 AM, Jabbar Azam wrote: Hello, I'm going to be building a 20 node cassandra cluster in one datacentre. The spec of the servers will roughly be dual core Celeron CPU, 256 GB SSD, 16GB RAM and two nics. Has anybody done any performance testing with this setup or have any gotcha's I should be aware of wrt to the hardware? I do realise the CPU is fairly low computational power but I'm going to assume the system is going to be IO bound hence the RAM and SSD's. Thanks Jabbar Azam -- *Colin Blower* *Software Engineer* Barracuda Networks Inc. +1 408-342-5576 (o)
Re: Any experience of 20 node mini-itx cassandra cluster
That's better. The SSD size is a bit small, and be warned that you will want to leave 50Gb to 100GB free to allow room for compaction (using the default size tiered). On the ram side you will want to run about 4GB (assuming cass 1.2) for the JVM the rest can be off heap Cassandra structures. This may not leave too much free space for the os page cache, but SSD may help there. Cheers - Aaron Morton Freelance Cassandra Consultant New Zealand @aaronmorton http://www.thelastpickle.com On 13/04/2013, at 4:47 PM, Jabbar Azam aja...@gmail.com wrote: What about using quad core athlon x4 740 3.2 GHz with 8gb of ram and 256gb ssds? I know it will depend on our workload but will be better than a dual core CPU. I think Jabbar Azam On 13 Apr 2013 01:05, Edward Capriolo edlinuxg...@gmail.com wrote: Duel core not the greatest you might run into GC issues before you run out of IO from your ssd devices. Also cassandra has other concurrency settings that are tuned roughly around the number of processors/cores. It is not uncommon to see 4-6 cores of cpu (600 % in top dealing with young gen garbage managing lots of sockets whatever. On Fri, Apr 12, 2013 at 12:02 PM, Jabbar Azam aja...@gmail.com wrote: That's my guess. My colleague is still looking at CPU's so I'm hoping he can get quad core CPU's for the servers. Thanks Jabbar Azam On 12 April 2013 16:48, Colin Blower cblo...@barracuda.com wrote: If you have not seen it already, checkout the Netflix blog post on their performance testing of AWS SSD instances. http://techblog.netflix.com/2012/07/benchmarking-high-performance-io-with.html My guess, based on very little experience, is that you will be CPU bound. On 04/12/2013 03:05 AM, Jabbar Azam wrote: Hello, I'm going to be building a 20 node cassandra cluster in one datacentre. The spec of the servers will roughly be dual core Celeron CPU, 256 GB SSD, 16GB RAM and two nics. Has anybody done any performance testing with this setup or have any gotcha's I should be aware of wrt to the hardware? I do realise the CPU is fairly low computational power but I'm going to assume the system is going to be IO bound hence the RAM and SSD's. Thanks Jabbar Azam -- Colin Blower Software Engineer Barracuda Networks Inc. +1 408-342-5576 (o)
Re: Any experience of 20 node mini-itx cassandra cluster
Thanks Aaron. Thanks Jabbar Azam On 14 April 2013 19:39, aaron morton aa...@thelastpickle.com wrote: That's better. The SSD size is a bit small, and be warned that you will want to leave 50Gb to 100GB free to allow room for compaction (using the default size tiered). On the ram side you will want to run about 4GB (assuming cass 1.2) for the JVM the rest can be off heap Cassandra structures. This may not leave too much free space for the os page cache, but SSD may help there. Cheers - Aaron Morton Freelance Cassandra Consultant New Zealand @aaronmorton http://www.thelastpickle.com On 13/04/2013, at 4:47 PM, Jabbar Azam aja...@gmail.com wrote: What about using quad core athlon x4 740 3.2 GHz with 8gb of ram and 256gb ssds? I know it will depend on our workload but will be better than a dual core CPU. I think Jabbar Azam On 13 Apr 2013 01:05, Edward Capriolo edlinuxg...@gmail.com wrote: Duel core not the greatest you might run into GC issues before you run out of IO from your ssd devices. Also cassandra has other concurrency settings that are tuned roughly around the number of processors/cores. It is not uncommon to see 4-6 cores of cpu (600 % in top dealing with young gen garbage managing lots of sockets whatever. On Fri, Apr 12, 2013 at 12:02 PM, Jabbar Azam aja...@gmail.com wrote: That's my guess. My colleague is still looking at CPU's so I'm hoping he can get quad core CPU's for the servers. Thanks Jabbar Azam On 12 April 2013 16:48, Colin Blower cblo...@barracuda.com wrote: If you have not seen it already, checkout the Netflix blog post on their performance testing of AWS SSD instances. http://techblog.netflix.com/2012/07/benchmarking-high-performance-io-with.html My guess, based on very little experience, is that you will be CPU bound. On 04/12/2013 03:05 AM, Jabbar Azam wrote: Hello, I'm going to be building a 20 node cassandra cluster in one datacentre. The spec of the servers will roughly be dual core Celeron CPU, 256 GB SSD, 16GB RAM and two nics. Has anybody done any performance testing with this setup or have any gotcha's I should be aware of wrt to the hardware? I do realise the CPU is fairly low computational power but I'm going to assume the system is going to be IO bound hence the RAM and SSD's. Thanks Jabbar Azam -- *Colin Blower* *Software Engineer* Barracuda Networks Inc. +1 408-342-5576 (o)
Any experience of 20 node mini-itx cassandra cluster
Hello, I'm going to be building a 20 node cassandra cluster in one datacentre. The spec of the servers will roughly be dual core Celeron CPU, 256 GB SSD, 16GB RAM and two nics. Has anybody done any performance testing with this setup or have any gotcha's I should be aware of wrt to the hardware? I do realise the CPU is fairly low computational power but I'm going to assume the system is going to be IO bound hence the RAM and SSD's. Thanks Jabbar Azam
Re: Any experience of 20 node mini-itx cassandra cluster
If you have not seen it already, checkout the Netflix blog post on their performance testing of AWS SSD instances. http://techblog.netflix.com/2012/07/benchmarking-high-performance-io-with.html My guess, based on very little experience, is that you will be CPU bound. On 04/12/2013 03:05 AM, Jabbar Azam wrote: Hello, I'm going to be building a 20 node cassandra cluster in one datacentre. The spec of the servers will roughly be dual core Celeron CPU, 256 GB SSD, 16GB RAM and two nics. Has anybody done any performance testing with this setup or have any gotcha's I should be aware of wrt to the hardware? I do realise the CPU is fairly low computational power but I'm going to assume the system is going to be IO bound hence the RAM and SSD's. Thanks Jabbar Azam -- *Colin Blower* /Software Engineer/ Barracuda Networks Inc. +1 408-342-5576 (o)
Re: Any experience of 20 node mini-itx cassandra cluster
That's my guess. My colleague is still looking at CPU's so I'm hoping he can get quad core CPU's for the servers. Thanks Jabbar Azam On 12 April 2013 16:48, Colin Blower cblo...@barracuda.com wrote: If you have not seen it already, checkout the Netflix blog post on their performance testing of AWS SSD instances. http://techblog.netflix.com/2012/07/benchmarking-high-performance-io-with.html My guess, based on very little experience, is that you will be CPU bound. On 04/12/2013 03:05 AM, Jabbar Azam wrote: Hello, I'm going to be building a 20 node cassandra cluster in one datacentre. The spec of the servers will roughly be dual core Celeron CPU, 256 GB SSD, 16GB RAM and two nics. Has anybody done any performance testing with this setup or have any gotcha's I should be aware of wrt to the hardware? I do realise the CPU is fairly low computational power but I'm going to assume the system is going to be IO bound hence the RAM and SSD's. Thanks Jabbar Azam -- *Colin Blower* *Software Engineer* Barracuda Networks Inc. +1 408-342-5576 (o)
Re: Any experience of 20 node mini-itx cassandra cluster
Duel core not the greatest you might run into GC issues before you run out of IO from your ssd devices. Also cassandra has other concurrency settings that are tuned roughly around the number of processors/cores. It is not uncommon to see 4-6 cores of cpu (600 % in top dealing with young gen garbage managing lots of sockets whatever. On Fri, Apr 12, 2013 at 12:02 PM, Jabbar Azam aja...@gmail.com wrote: That's my guess. My colleague is still looking at CPU's so I'm hoping he can get quad core CPU's for the servers. Thanks Jabbar Azam On 12 April 2013 16:48, Colin Blower cblo...@barracuda.com wrote: If you have not seen it already, checkout the Netflix blog post on their performance testing of AWS SSD instances. http://techblog.netflix.com/2012/07/benchmarking-high-performance-io-with.html My guess, based on very little experience, is that you will be CPU bound. On 04/12/2013 03:05 AM, Jabbar Azam wrote: Hello, I'm going to be building a 20 node cassandra cluster in one datacentre. The spec of the servers will roughly be dual core Celeron CPU, 256 GB SSD, 16GB RAM and two nics. Has anybody done any performance testing with this setup or have any gotcha's I should be aware of wrt to the hardware? I do realise the CPU is fairly low computational power but I'm going to assume the system is going to be IO bound hence the RAM and SSD's. Thanks Jabbar Azam -- *Colin Blower* *Software Engineer* Barracuda Networks Inc. +1 408-342-5576 (o)
