mirror of
https://gitlab.torproject.org/tpo/core/tor.git
synced 2024-11-27 13:53:31 +01:00
86 lines
3.3 KiB
Plaintext
86 lines
3.3 KiB
Plaintext
Most operating systems limit an amount of TCP sockets that can be used
|
|
simultaneously. It is possible for a busy Tor relay to run into these
|
|
limits, thus being unable to fully utilize the bandwidth resources it
|
|
has at its disposal. Following system-specific tips might be helpful
|
|
to alleviate the aforementioned problem.
|
|
|
|
Linux
|
|
-----
|
|
|
|
Use 'ulimit -n' to raise an allowed number of file descriptors to be
|
|
opened on your host at the same time.
|
|
|
|
FreeBSD
|
|
-------
|
|
|
|
Tune the followind sysctl(8) variables:
|
|
* kern.maxfiles - maximum allowed file descriptors (for entire system)
|
|
* kern.maxfilesperproc - maximum file descriptors one process is allowed
|
|
to use
|
|
* kern.ipc.maxsockets - overall maximum numbers of sockets for entire
|
|
system
|
|
* kern.ipc.somaxconn - size of listen queue for incoming TCP connections
|
|
for entire system
|
|
|
|
See also:
|
|
* https://www.freebsd.org/doc/handbook/configtuning-kernel-limits.html
|
|
* https://wiki.freebsd.org/NetworkPerformanceTuning
|
|
|
|
Mac OS X
|
|
--------
|
|
|
|
Since Mac OS X is BSD-based system, most of the above hold for OS X as well.
|
|
However, launchd(8) is known to modify kern.maxfiles and kern.maxfilesperproc
|
|
when it launches tor service (see launchd.plist(5) manpage). Also,
|
|
kern.ipc.maxsockets is determined dynamically by the system and thus is
|
|
read-only on OS X.
|
|
|
|
OpenBSD
|
|
-------
|
|
|
|
Because OpenBSD is primarily focused on security and stability, it uses default
|
|
resource limits stricter than those of more popular Unix-like operating systems.
|
|
|
|
OpenBSD stores a kernel-level file descriptor limit in the sysctl variable
|
|
kern.maxfiles. It defaults to 7,030. To change it to, for example, 16,000 while
|
|
the system is running, use the command 'sudo sysctl kern.maxfiles=16000'.
|
|
kern.maxfiles will reset to the default value upon system reboot unless you also
|
|
add 'kern.maxfiles=16000' to the file /etc/sysctl.conf.
|
|
|
|
There are stricter resource limits set on user classes, which are stored in
|
|
/etc/login.conf. This config file also allows limit sets for daemons started
|
|
with scripts in the /etc/rc.d directory, which presumably includes Tor.
|
|
|
|
To increase the file descriptor limit from its default of 1,024, add the
|
|
following to /etc/login.conf:
|
|
|
|
tor:\
|
|
:openfiles-max=13500:\
|
|
:tc=daemon:
|
|
|
|
Upon restarting Tor, it will be able to open up to 13,500 file descriptors.
|
|
|
|
This will work *only* if you are starting Tor with the script /etc/rc.d/tor. If
|
|
you're using a custom build instead of the package, you can easily copy the rc.d
|
|
script from the Tor port directory. Alternatively, you can ensure that the Tor's
|
|
daemon user has its own user class and make a /etc/login.conf entry for it.
|
|
|
|
High-bandwidth relays sometimes give the syslog warning:
|
|
|
|
/bsd: WARNING: mclpools limit reached; increase kern.maxclusters
|
|
|
|
In this case, increase kern.maxclusters with the sysctl command and in the file
|
|
/etc/sysctl.conf, as described with kern.maxfiles above. Use 'sysctl
|
|
kern.maxclusters' to query the current value. Increasing by about 15% per day
|
|
until the error no longer appears is a good guideline.
|
|
|
|
Disclaimer
|
|
----------
|
|
|
|
Do note that this document is a draft and above information may be
|
|
technically incorrect and/or incomplete. If so, please open a ticket
|
|
on https://gitlab.torproject.org or post to tor-relays mailing list.
|
|
|
|
Are you running a busy Tor relay? Let us know how you are solving
|
|
the out-of-sockets problem on your system.
|