> i want to know which cassandra client is better？ Go with Astynax or Native Binary, they are both under active development and support by a vendor / large implementor.
Cheers ----------------- Aaron Morton Freelance Cassandra Consultant New Zealand @aaronmorton http://www.thelastpickle.com On 7/05/2013, at 7:03 AM, Derek Williams <de...@fyrie.net> wrote: > Also have to keep in mind that it should be rare to only use a single socket > since you are usually making at least 1 connection per node in the cluster > (or local datacenter). There is also nothing enforcing that a single client > cannot open more than 1 connection to a node. In the end it should come down > to which protocol implementation is faster. > > > On Mon, May 6, 2013 at 11:58 AM, Aaron Turner <synfina...@gmail.com> wrote: > From my experience, your NIC buffers generally aren't the problem (or at > least it's easy to tune them to fix). It's TCP. Simply put, your raw NIC > throughput > single TCP socket throughput on most modern hardware/OS > combinations. This is especially true as latency increases between the two > hosts. This is why Bittorrent or "download accellerators" are often faster > then just downloading a large file via your browser or ftp client- they're > running multiple TCP connections in parallel compared to only one. > > TCP is great for reliable, bi-directional, stream based communication. Not > the best solution for high throughput though. UDP is much better for that, > but then you loose all the features that TCP gives you and so then people end > up re-inventing the wheel (poorly I might add). > > So yeah, I think the answer to the question of "which is faster" the answer > is "it depends on your queries". > > > > On Mon, May 6, 2013 at 10:24 AM, Hiller, Dean <dean.hil...@nrel.gov> wrote: > You have me thinking more. I wonder in practice if 3 sockets is any faster > than 1 socket when doing nio. If your buffer sizes were small, maybe that > would be the case. Usually the nic buffers are big so when the selector > fires it is reading from 3 buffers for 3 sockets or 1 buffer for one socket. > In both cases, all 3 requests are there in the buffers. At any rate, my > belief is it probably is still basically parallel performance on one socket > though I have not tested my theory…..My theory being the real bottleneck on > performance being the work cassandra has to do on the reads and such. > > What about 20 sockets then(like someone has a pool). Will it be any > faster…not really sure as in the end you are still held up by the real > bottleneck of reading from disk on the cassandra side. We went to 20 threads > in one case using 20 sockets with astyanax and received no performance > improvement(synchronous but more sockets did not improve our performance). > Ie. It may be the case 90% of the time, one socket is just as fast as > 10/20…..I would love to know the truth/answer to that though. > > Later, > Dean > > > From: Aaron Turner <synfina...@gmail.com<mailto:synfina...@gmail.com>> > Reply-To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org>" > <user@cassandra.apache.org<mailto:user@cassandra.apache.org>> > Date: Monday, May 6, 2013 10:57 AM > To: cassandra users > <user@cassandra.apache.org<mailto:user@cassandra.apache.org>> > Subject: Re: hector or astyanax > > Just because you can batch queries or have the server process them out of > order doesn't make it fully "parellel". You're still using a single TCP > connection which is by definition a serial data stream. Basically, if you > send a bunch of queries which each return a large amount of data you've > effectively limited your query throughput to a single TCP connection. Using > Thrift, each query result is returned in it's own TCP stream in *parallel*. > > Not saying the new API isn't great, doesn't have it's place or may have > better performance in certain situations, but generally speaking I would > refrain from making general claims without actual benchmarks to back them up. > I do completely agree that Async interfaces have their place and have > certain advantages over multi-threading models, but it's just another tool to > be used when appropriate. > > Just my .02. :) > > > > On Mon, May 6, 2013 at 5:08 AM, Hiller, Dean > <dean.hil...@nrel.gov<mailto:dean.hil...@nrel.gov>> wrote: > I was under the impression that it is multiple requests using a single > connectin PARALLEL not serial as they have request ids and the responses do > as well so you can send a request while a previous request has no response > just yet. > > I think you do get a big speed advantage from the asynchronous nature as you > do not need to hold up so many threads in your webserver while you have > outstanding requests being processed. The thrift async was not exactly async > like I am suspecting the new java driver is, but have not verified(I hope it > is) > > Dean > > From: Aaron Turner > <synfina...@gmail.com<mailto:synfina...@gmail.com><mailto:synfina...@gmail.com<mailto:synfina...@gmail.com>>> > Reply-To: > "user@cassandra.apache.org<mailto:user@cassandra.apache.org><mailto:user@cassandra.apache.org<mailto:user@cassandra.apache.org>>" > > <user@cassandra.apache.org<mailto:user@cassandra.apache.org><mailto:user@cassandra.apache.org<mailto:user@cassandra.apache.org>>> > Date: Sunday, May 5, 2013 5:27 PM > To: cassandra users > <user@cassandra.apache.org<mailto:user@cassandra.apache.org><mailto:user@cassandra.apache.org<mailto:user@cassandra.apache.org>>> > Subject: Re: hector or astyanax > > > > On Sun, May 5, 2013 at 1:09 PM, Derek Williams > <de...@fyrie.net<mailto:de...@fyrie.net><mailto:de...@fyrie.net<mailto:de...@fyrie.net>>> > wrote: > The binary protocol is able to multiplex multiple requests using a single > connection, which can lead to much better performance (similar to HTTP vs > SPDY). This is without comparing the performance of thrift vs binary > protocol, which I assume the binary protocol would be faster since it is > specialized for cassandra requests. > > > Curious why you think multiplexing multiple requests over a single connection > (serial) is faster then multiple requests over multiple connections > (parallel)? > > And isn't Thrift a binary protocol? > > > -- > Aaron Turner > http://synfin.net/ Twitter: @synfinatic > http://tcpreplay.synfin.net/ - Pcap editing and replay tools for Unix & > Windows > Those who would give up essential Liberty, to purchase a little temporary > Safety, deserve neither Liberty nor Safety. > -- Benjamin Franklin > "carpe diem quam minimum credula postero" > > > > -- > Aaron Turner > http://synfin.net/ Twitter: @synfinatic > http://tcpreplay.synfin.net/ - Pcap editing and replay tools for Unix & > Windows > Those who would give up essential Liberty, to purchase a little temporary > Safety, deserve neither Liberty nor Safety. > -- Benjamin Franklin > "carpe diem quam minimum credula postero" > > > > -- > Aaron Turner > http://synfin.net/ Twitter: @synfinatic > http://tcpreplay.synfin.net/ - Pcap editing and replay tools for Unix & > Windows > Those who would give up essential Liberty, to purchase a little temporary > Safety, deserve neither Liberty nor Safety. > -- Benjamin Franklin > "carpe diem quam minimum credula postero" > > > > -- > Derek Williams
