I'm on Linux. I've also tried to use agents but there was no difference (but I'm not doing frequent requests to the same server many times).
I have some progress with this problem: I wrongly assumed Node uses truly asynchronous DNS resolution via c-ares. This turned out not to be the case - the documentation says it uses getaddrinfo(3) system call in a thread pool. My hypothesis is that this is the same thread pool that handles I/O and I've hit some limit of this thread pool with DNS resolution, so the requests there - for both DNS and I/O - have been queued. I switched to doing the DNS resolution using dns.resolve4 which uses c- ares and now the delay in disk I/O is happening at much higher load in terms of requests per second; the network may actually be saturated. But it still happens. Nikola On Mar 5, 2:45 pm, mscdex <[email protected]> wrote: > On Mar 5, 4:43 am, Nikola Toshev <[email protected]> wrote: > > > Http requests also begin to take a while to complete even though the > > network pipe is not saturated. I'm using local DNS caching and it does > > help somewhat, but I'm still not able to go beyond 100 or so http > > requests per second, with CPU usage <10% and network not being > > saturated. I use agent:false for the http requests. Again, I expect to > > be able to saturate the network connection before such slowdowns start > > happening. > > What OS are you on and have you tried using agent(s) instead in order > to reuse sockets? -- Job Board: http://jobs.nodejs.org/ Posting guidelines: https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines You received this message because you are subscribed to the Google Groups "nodejs" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/nodejs?hl=en?hl=en
