Thanks for getting back. Here is some background to the application in its
current state -

The application has X worker threads that receives 1000s of concurrent
requests per second.

As part of handling these incoming requests, the X worker threads need to
make a callout to an external HTTP server. This callout typically takes up
to 100 ms.

Currently, the X worker threads have implemented this by using a
curl_easy_handle per thread, i.e. a connection per thread that is
continuously making callouts and handling the responses in the callback
function CURLOPT_WRITEFUNCTION.

However, this also means that the application is not doing much except
waiting on external HTTP server. The CPU is hardly utilised.

In order to overcome this, I am planning to use the curl multi interface.
So each of the X curl easy handles from X threads will be added to the curl
multi handle.

Does that sound a reasonable thing to do?

Regards
Raj

On Thu, Jul 9, 2015 at 11:38 PM, Ray Satiro via curl-library <
curl-library_at_cool.haxx.se> wrote:

> On 7/9/2015 5:19 PM, Rajalakshmi Iyer wrote:
>
>> Is it appropriate to have a global CURL multi handle to which easy
>> handles are added by different threads in an application?
>>
>
> It's possible but I don't know whether it's appropriate for you. I'm
> thinking back to what you posted on the list a few days ago and it sounded
> really like you may be experiencing some connectivity issue that is/was
> causing problems. That seems like the issue to address rather than rewrite
> your code. Also it was mentioned you can share DNS and such (but frankly
> I'm skeptical it would help in this case). Anyway, if that's a non-starter
> then please review [1] and "Only use one handle in one thread at any time."
>
>
> [1]: http://curl.haxx.se/libcurl/c/libcurl-tutorial.html#Multi-threading
>
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