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by majewsky 3235 days ago
I have a Synapse running (among other things) on a 1/1 VM. It's at the top of `top` (heh) when sorting by memory:

  PID USER      PR  NI    VIRT    RES %CPU %MEM     TIME+ S COMMAND                                                                                                                                                 
  486 synapse   20   0  510,1m  81,7m  0,0  8,2   3:03.73 S python2.7
  ...
There are six user accounts on that Synapse and few activity (less than 100 messages per day).

When I first installed it to play around with it, I joined #matrix:matrix.org and it brought Synapse to a grinding halt. Took quite some time to catch up with the thousands of peers it suddenly had to federate with, and I ultimately cleared Synapse's database to make it forget about all these peers.

For comparison, I also have a Prosody (i.e. an XMPP server) on the same box, which has about 10 user accounts and my own account is joined to a few moderately busy MUCs, so the number of messages is at least one order of magnitude higher. Yet memory usage is about one order of magnitude smaller (CPU usage is too infrequent to compare, but look at the "TIME" column for an initial comparison):

  $ psgrep 'prosody\|synapse'
  USER       PID %CPU %MEM    VSZ   RSS TTY      STAT START   TIME COMMAND
  synapse    486  0.1  8.1 522332 83664 ?        Ssl  Aug13   3:04 /usr/bin/python2.7 -m synapse.app.homeserver --config-path=/etc/synapse/homeserver.yaml --log-config=/etc/synapse/log_config.yaml
  prosody    574  0.0  1.0  52408 10476 ?        S    Aug13   0:27 lua5.1 /usr/lib/prosody/../../bin/prosody
1 comments
ryukafalz 3235 days ago
Synapse does a lot more than Prosody though. If a Prosody server hosting a MUC goes down, the MUC is down. If the Matrix homeserver that created a room goes down, the room's still there as long as there are other servers participating. That decentralization does have its tradeoffs.

It's also the first Matrix server, so there's that. Its replacement is in progress: https://github.com/matrix-org/dendrite

link
majewsky 3234 days ago
Oh nice. That should have a lot less footprint indeed, both in terms of CPU usage and # of dependencies. (Not entirely sure about memory usage, but that should also be better for a compiled language.)
link