cayenne-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Aristedes Maniatis <...@maniatis.org>
Subject Re: Closing Cayennes' DataContext
Date Thu, 08 Jan 2015 23:04:21 GMT
On 9/01/2015 4:03am, Michael Gentry wrote:
> Also, what kind of load do you have on your system?  Our connection pools
> are rarely larger than 25-50 and work just fine.  10,000 connections smells
> to me of a larger problem.

I agree. I read an interesting article about the tradeoff between queuing and threading. That
is, if you get lots of requests are you better creating lots and lots of threads to handle
them all concurrently, or queuing the requests (eg. by having a connection pool of only about
30 connections) and handling them 30 at a time.

The author of the article I can't right now find was of the opinion that most people have
way too many connections in their pool. The number of connections should be closer (within
an order of magnitude) to the number of cores in the CPU. For example, mysql creates a separate
unix thread for every connection and that scales poorly over about 60. I think this is improved
in mysql 5.7, but I've not tried it. [1]

Ari



[1] http://dev.mysql.com/doc/refman/5.6/en/thread-pool-plugin.html

-- 
-------------------------->
Aristedes Maniatis
GPG fingerprint CBFB 84B4 738D 4E87 5E5C  5EFA EF6A 7D2E 3E49 102A

Mime
View raw message