Re: [MooseFS-Users] How many clients dose MFS max support?

[Jakub Kruszona-Z. <jak...@ge...>]

On 19 Sep, 2015, at 3:02, pen...@ic... wrote:

> That's great.
> But master is single thread, I think this is one of a  limitation to master.

Not exactly. Very often single threaded apps are as fast as multithreaded (sometimes even faster - and always much safer and much less buggy). In multithreaded apps CPU spends a lot of time on synchronization. Also whole architecture of application is usually much worse.

Davies is right - to handle thousands of clients the most important improvement is to change poll to epoll/kqueue and it is on our roadmap. This should speed up master significantly in case of huge number of clients/chunkservers.

> 
> pen...@ic...
>  
> From: Davies Liu
> Date: 2015-09-19 01:21
> To: Aleksander Wieliczko
> CC: pen...@ic...; moosefs-users
> Subject: Re: [MooseFS-Users] How many clients dose MFS max support?
> I think MFS can't scale well if there are more than 2k clients. We saw
> the CPU usage of master went to almost 100% with about 1k clients and
> not high traffic.
>  
> In order to scale to thousands of clients, MFS should use
> epoll/kqueue. I have a branch that use epoll instead of poll:
> https://github.com/davies/moosefs/commits/douban
>  
> On Fri, Sep 18, 2015 at 2:31 AM, Aleksander Wieliczko
> <ale...@mo...> wrote:
> > Hi
> > All depends.
> > Question is how many clients you want to have and how many operations they
> > will perform on one master?
> >
> > We have instances with about 300 client in production environment.
> > In our software we don't have any client connection limits, but number of
> > parallel connections close to 10 000 creates different level of problem.
> >
> > Best regards
> > Aleksander Wieliczko
> > Technical Support Engineer
> > MooseFS.com
> >
> > On 18.09.2015 09:20, pen...@ic... wrote:
> >
> > hi all:
> >
> >     How many clients does Moosefs max support?
> >
> >     Thanks for your help.
> >
> >     best regards.
> > ________________________________
> > pen...@ic...
> >
> >
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>  
>  
>  
> --
> - Davies
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-- 
Pozdrawiam,
Jakub Kruszona-Zawadzki
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