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Subject: Re: [Boost-users] [Asio] Measuring and improving SSL servier scalability
From: Konrad Zemek (konrad.zemek_at_[hidden])
Date: 2015-08-18 12:03:48

On 17.08.2015 22:54, Eric Prud'hommeaux wrote:
> * Konrad Zemek <konrad.zemek_at_[hidden]> [2015-08-16 15:57+0200]
>> Hi all,
>> I've built a few different Asio-based SSL servers in my career, but in
>> my recent project the performance and resource-efficiency was paramount
>> (as it's a library project), so I benchmarked it to make sure.
>> Long story short, when benchmarking I found out that OpenSSL's error
>> handling is a *very* serious bottleneck when scaling Asio+SSL over
>> multiple threads. This can be "fixed", e.g. by using BoringSSL instead
>> of OpenSSL, as BoringSSL uses thread-local storage for error data
>> instead of locking a global mutex.
>> As I didn't find any resources discussing bad Asio+SSL multithreaded
>> performance (aside of one or two messages somewhere on this mailing list
>> that complained about the problem; unfortunately I can't seem to find
>> them right now), I've written up my knowledge into a blog post [1]. I
>> believe it might be very useful to anyone who wants to build a
>> multi-threaded SSL server/client on top of Asio.
> The 0.11-devel brance of has support for SSL. Any idea how that stacks
> up?

Some words seem to be missing from this sentence (most notably name of
a project); could you clarify?


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