LDAP timeouts during failure conditions

Phil Mayers p.mayers at imperial.ac.uk
Thu Jun 30 19:34:19 CEST 2011

On 30/06/11 16:45, Alexander Clouter wrote:
> Phil Mayers<p.mayers at imperial.ac.uk>  wrote:
>> On that latter topic: I do wonder if we might start running into
>> problems with fd_set size limitations now that "master" supports TCP
>> sockets. Eduroam sites (e.g. us) using radius-over-TLS and DNS-based
>> autodiscovery could, conceivably, have many tens of TCP connections
>> open at any given time. But an epoll event core is probably pretty
>> trivial, given that Alan has factored the existing loop cleanly.
> epoll is for when you have 1000's of FD's...not less than 100.  epoll is

I'll let JP reply for me:


tl;dr - select has a microscopic advantage over epoll for very tiny 
numbers of FDs, but it's negligible in modern systems. epoll scales 
better and has far, far better worst-case performance, as well as 
handling many idle connections better. There's absolutely no discernible 
issue with using epoll over select in any app except a micro-benchmark 
designed to test syscall latency in the case with small numbers of FDs.

So, I disagree completely ;o)

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