I believe the runtime uses select(), which has a hard limit (enforced by the kernel) that the maximum file descriptor id be 1023. (select() uses bitmasks and there is a limit on the size of a bitmask; see FD_SETSIZE.)
I understand. Thank you.
Reduce this to 1024, otherwise the runtime will eventually find itself dealing with file descriptors beyond the select() limit mentioned above. Someone with more knowledge of the Haskell runtime will have to advise as to possible ways around it if you really need more than 1024 file descriptors.
I used to execute my server with the limit of 1024 since this is the default limit of my machine. At that time, I suffered from the following errors: rpf: user error (Cannot create OS thread.) rpf: accept: resource exhausted (Too many open files) So, I pushed the limit to 65536. I don't believe my server receives 1024 connections at once. So, I guess file descriptors leak. Does anyone know what happens when a TCP connection is reset by the peer and its handle disappears. Does the file descriptor bound to the handle leak? --Kazu