Our installation at https://lists.rootsweb.ancestry.com has around 33,000 lists and somewhere around 1.5 million members. We have lists with 5,000+ members.
Note that I haven't tried any mass subscriptions. When we upgraded from mailman 2 to mailman 3, we used the old .pck files and ran the import on each of the lists. It did take about 6 weeks to do the full import all 33,000 lists. I'm not joking.
As for sending messages - there isn't any problem sending that many messages out, but then we are also not trying to subscribe list members at the time. We are, though, in the process of importing the old archives from our old mailman 2 system. This doesn't seem to affect the rest of the system.
We have seen some inefficiencies in the new system, such as the front page of postorius - loading all of the information for 200 lists (if the user set the "lists per page" to 200) was bringing down the system. We have our own metadata system to be able to search for lists by state/region/surname (ours is a genealogy mailing list system), so we had to replace the front page with our own "find a list" functionality.
The other main problem was the page where a user can see what lists they subscribe to. That page was also a denial of service if the user had several hundred lists they are subscribed to. And for a genealogy mailing list system, this is common.
We have actually ended up creating our own API layer (only accessible on the local machine) and make certain calls to it for the most painful of the issues. One of these days (when we get a moment to breathe) we are going to post some of our changes to the project so that we can ditch our own API and just use the internal REST API.
To be fair, the inefficiencies are not necessarily with mailman or the rest API itself - but with Postorius making hundreds of calls to load a single page. Though if the API supported loading multiple lists at once instead of having to load them serially, that might help as well.
So while we have not seen any timeout issues on the call to mass subscribe users, we HAVE found several other calls that are effectively a denial of service and have gotten around them ourselves, with plans to contribute to the project in the near future.
On Tue, Apr 24, 2018 at 8:47 AM, Mark Sapiro firstname.lastname@example.org wrote:
On 04/24/2018 12:36 AM, Abhilash Raj wrote:
On Mon, Apr 23, 2018, at 10:41 PM, Jonas Felber wrote:
We also have a problem with sending out emails to "large" (>50) groups, as they seem to not getting sent out at all. Do you have any idea what the problem here could be?
Which MTA are you using? What do you see in mailman's logs and MTA's logs?
I haven't seen this kind of problem before with Mailman 3. This very list is hosted using Mailman 3 and I believe has more than 50 subscribers.
Nor have I seen this issue. This list currently has 158 non-digest members. There are several @python.org Mailman 3 lists with over 100 non-digest members including the active email@example.com list with 301 members, and I have gotten no reports of an issue like this.
Also, there are over 600 lists at https://lists.fedoraproject.org/, and I don't think this is an issue there either.
-- Mark Sapiro firstname.lastname@example.org The highway is for gamblers, San Francisco Bay Area, California better use your sense - B. Dylan
Mailman-users mailing list email@example.com https://lists.mailman3.org/mailman3/lists/mailman-users.mailman3.org/