Zwift freezing/crashing

So, after riding  stage 4 of the TdZ today, it seems they have disabled  some features during group rides (rankings, chat), presumably to lessen server load.

Worth trying again and seeing if you have better luck?  Seemed pretty stable to me.

In normal use, Zwift communicates the position of the nearest 200(?) riders, which may be rendered on your device's screen. This communication is not at a huge data rate - certainly not enough to overload the average broadband connection. When less than great home wi-fi is incorporated into the mix, there may be additional bandwidth resctrictions and/or latency between that data being sent and the user receiving it. Bear in mind that the user also communicates their power, heart rate, cadence, position on track?, speed(?) info back to Zwift, who then take this data and send it out to whoever has you within their 200 rider radius. ANT+/bluetooth interference and drop outs won't help.

I don't think the raw number crunching of this user information is actually hugely computationally expensive, and Zwift will be able to spin up multiple servers very rapidly to cope with changes in load. The distribution of this information over a variety of networks may well be more of an issue.

I don't know what happens when rider density is really high, as in these multi-thousand user start events, but I guess you might get information on more than the default number of nearest users if they're really close.

For the CPU and graphics card of the user's device, rendering all these other users will cause more load, and result in a drop in frame rate. Combine this with lags between data communicated to and from the user that could result from increased local and remote processing requirements, and systems that will normally be just about usable are most likely to drop into the unusable territory.

The majority of users have a good experience in these events, it's just that this sort of issue is most likely to raise its head in this type of event. In some cases it may be Zwift's issue, most of the time I think users are hitting a limitation of their setup.

Basically, I think it's more likely you'll see these slowdowns if your CPU, GPU, Wifi, broadband or ANT+/Bluetooth signal is less than optimal. The problem for many is identifying which one is the limiting factor. Maybe Zwift could help by providing some sort of testing program, which would help point the way, until then, there's https://zwiftalizer.com/ which is the best way to analyse log files to see if there's anything obvious.

Set graphics to 720p and ensure good internet connection.  Ive had less issues now I use mobile data link at 60mb connection speed.  I have a decent mid range pc with plenty of ram and good graphics, well enough to run 1080p and still be able to race in TDZ.  I think there were 4000 riders on my particular event plus normal zwift users. Ive seen 10,000 users at once but dont get full crashes, just short period dropouts and it always returns without losing ride/race.

For these recent tour stages i've found the same on wi-fi but no problems with a wired connection. Seems to be a widely held view on the forums too. Also switching to the low graphics setting when doing a massive group ride seems to help.

Ah, I had issues last night with a very juddery picture and slow to update the images on the screen - ran laptop through tv intially & then just on laptop but same resuts.  I thought it was just our crappy Sky broadband!

I thought people did indoor cycling as they wouldnt experience freezing or the chance of crashing?

Actually, another possibility, if it's properly crashing rather than just glitching (e.g. riders dissappearing, wrong world etc), it might be worth trying to turn down the graphics settings.  I can't imagine that it's optimised for the 2-3,000 rider groups that have been seen lately.

I suspect that there will be a number of lessons to be learned from the current tour!

One thing I have found that has helped with the crashes is using a router that allows you to priotise devices as I compete at home with avid streamers

Rode 21miles using the Zwift Windows app on Windows 8.1 (yes I know) on Monday night and no problems. Companion app on Android A3 did refuse to show the map although everything else worked fine i.e. dashboard, zwifters etc.

Turbo and pc are in the conservatory and running over wi-fi.

there was over 12,000 concurrent users on there the other night which is the most i've ever seen. I was in a race and had issues with everyone else in the race disappearing from time to time, which didn't exactly help with staying in a group. didn't crash though.

Same here, last few rides have all frozen & crashed & lost.

I run mine through the companion app on a laptop & galaxy S9 & the companion app is shutting down & restarting literally every 30 secs.

I just assumed it was me & am looking into going for the Ant+ dongle setup as the general consensus seems it’s a more reliable connection.

1st world problems indeed but as my weekend bike & turbo bike are one in the same & my missus allows me to leave the turbo setup in the living room during the week,

I am not going to go cycling out during the evenings then spend an hour cleaning it to use on the turbo next time. The least I can do is play ball & keep the bike clean whilst it’s in the house.

Were you riding the Tour de Zwift or seeing a lot of Tour riders?  It seems (based on the Zwift forums) that they have broken records for simultaneous users several times in the last week and it's putting a bit of a strain on the whole thing.

On Apple TV it self-limits to displaying 100 riders for performance reasons, but I don't believe that limit is imposed on other device types, so this might be the problem if everything else is unchanged, given it only started a week ago (when the Tour started).