---
summary: Room membership count lies in many different ways.
---
created: 2015-03-12 12:30:54.0
creator: matthew
description: |-
  The membership count reported in Recents doesn't match that in Public Rooms - and can also be out of sync with the size of the membership list and the actual observed current members of a room:

  [11:13]  <M-testme> [08:35:06] Hi guys ...
  [11:13]  <M-testme> [08:36:12] Speaking of playing with the api, I'm just now playing with it. I have to newly created rooms, and when querying /publicRooms I get (among others) num_joined_members: 49
  [11:13]  <M-testme> [08:36:27] Where do these other 48 members come from?
  [11:13]  <M-matthew> [09:24:20] weird
  [11:13]  <M-matthew> [09:24:27] sounds like a bug
  [11:13]  <M-matthew> [09:24:54] perhaps you keep rejoining it as the same user and the count keeps increasing?
  [11:13]  <M-kegan> [09:26:44] seems likely: most of the default clients won't rejoin if it remembers it had already joined, but if you're playing with the API then it is possible that this is a failure case we aren't seeing
  [11:13]  * M-kegan [09:27:08] still doesn't quite get the rationale behind not treating multiple joins as noops
  [11:13]  <M-matthew> [09:27:29] it's a bug surely?
  [11:13]  <M-Tor> [09:28:09] haven't we already established that the public rooms number of users is way off?
  [11:13]  <M-kegan> [09:32:24] iirc federation needs multiple joins for something. It may be a bug that those are being sent to the client maybe, but I don't know.
  [11:13]  <M-kegan> [09:32:32] and yes, it is way off Tor
  [11:13]  <M-testme> [09:35:02] Looks like a bug to me, I queried directly after creating the room.
  [11:13]  <M-matthew> [09:47:52] that's even stranger then.

  [11:29]  <M-Tor> hm, my script and angular is now off by one for nicks in this channel :p
  [11:29]  <LeoNerd> Counting yourself?
  [11:29]  <M-Tor> better than before, wonder who it is that can't count
  [11:29]  <M-Tor> I am in my script, yes

  [12:07]  <M-matthew> Erik: any inspiration on the room count nightmare?
  [12:08]  <M-matthew> *room member count
  [12:28]  <M-erikj> Not really
  [12:28]  <M-erikj> could be the current_state_events table getting out of sync with the actual state
  [12:29]  <M-erikj> or a table is returning duplicate rows somewhere

  etc.
id: '11201'
key: SYN-307
number: '307'
priority: '2'
project: '10000'
reporter: matthew
status: '1'
type: '1'
updated: 2016-11-07 18:27:49.0
votes: '0'
watches: '2'
workflowId: '11301'
---
actions:
- author: richvdh
  body: 'Migrated to github: https://github.com/matrix-org/synapse/issues/1294'
  created: 2016-11-07 18:27:49.0
  id: '13615'
  issue: '11201'
  type: comment
  updateauthor: richvdh
  updated: 2016-11-07 18:27:49.0