I can't be arsed to bug report things thoroughly that other people have found in the past and don't report this time. But I still want to put it on here anyway.

Issues:
- Allegedly /idleserver on causes 10 ms extra lag for every client
- /idleserver off causes slower level cycling (because you have to wait for the host to get to the next level, and an afk spectating host has a score screen that the host does not skip.)
- /idleserver on and spectating your server sucks, because you can't follow players. Any spying or trying to confirm suspicion of people cheating can not be handled. Ideally the spectating itself is the same for both modes and drawing of tiles only happens for x minutes if the the host interacts with keys.

The added ms in idleserver mode is normal, since jj2 turns into a background process to conserve CPU power. This is not a bug that needs fixing, imo.

This seems to be three or four unrelated threads? Especially the 32-bit seems to have no connection to idle servers

cooba says: "an idle server should ideally be as close to a dedicated server mode as possible, and cheating detection should be an entirely different section that doesn't require the host's input"

Originally Posted by FawFul

- Allegedly /idleserver on causes 10 ms extra lag for every client

This is not caused by idleserver, it's caused by having the game minimized. You can have idleserver on without minimizing the game (and you can have the game minimized without idleserver on, which results in the same extra lag).

Originally Posted by Violet CLM

This seems to be three or four unrelated threads? Especially the 32-bit seems to have no connection to idle servers

Took that 32-bit one out and made a seperate thread. I'm not going through the effort of seperating the rest though. See opening line. Unfortunately JCF still does not allow me to change the thread titles.

Originally Posted by FawFul

- /idleserver off causes slower level cycling (because you have to wait for the host to get to the next level, and an afk spectating host has a score screen that the host does not skip.)
- /idleserver on and spectating your server sucks, because you can't follow players. Any spying or trying to confirm suspicion of people cheating can not be handled. Ideally the spectating itself is the same for both modes and drawing of tiles only happens for x minutes if the the host interacts with keys.

This is intended behavior. Idle server mode is not meant to be a special "spectator mode 2" available only to hosts. It is a mode intended for servers whose maintainers are not at the keyboard, might never be at the keyboard and, in fact, there might be no keyboard. Much like cooba's messages indicate, ideally, the game window would display nothing or next to nothing in idle server mode, since - in the scenarios it's intended for - there is nobody to display anything for (and sometimes no screen to display it on) and it's a waste of CPU cycles. So yes, spectating in idle server mode sucks; we discourage it, do not intend to improve it, and instead might intentionally make it even worse or impossible in the future. If you want to spectate the game, you should enable spectator mode.

When idle server mode is off, there is indeed a level end screen displayed to the host, because in that case the host is assumed to be at the keyboard and potentially happy to see that screen, like all other players. If the host is not at the keyboard, they should activate idle server mode - as explained above, that's exactly what it's for. If the host is unhappy to see the transition screen, they can press fire to skip it, like other players. Because of the way level transition actions are ordered, the server only sends the clients information about the next level once that transition screen expires, so in the remaining situation that the host is in fact at the keyboard and happy to watch the screen display the winners of the most recent game, everyone has to wait for it to finish. This is the one place where the behavior may be possible to improve. However, odds are, there's a lot of room for things breaking if clients enter a level before the server does, so it's a scary portion of the code to mess with, for limited benefit.

Originally Posted by Seren

This is intended behavior. Idle server mode is not meant to be a special "spectator mode 2" available only to hosts. It is a mode intended for servers whose maintainers are not at the keyboard, might never be at the keyboard and, in fact, there might be no keyboard. Much like cooba's messages indicate, ideally, the game window would display nothing or next to nothing in idle server mode, since - in the scenarios it's intended for - there is nobody to display anything for (and sometimes no screen to display it on) and it's a waste of CPU cycles. So yes, spectating in idle server mode sucks; we discourage it, do not intend to improve it, and instead might intentionally make it even worse or impossible in the future. If you want to spectate the game, you should enable spectator mode.

When idle server mode is off, there is indeed a level end screen displayed to the host, because in that case the host is assumed to be at the keyboard and potentially happy to see that screen, like all other players. If the host is not at the keyboard, they should activate idle server mode - as explained above, that's exactly what it's for. If the host is unhappy to see the transition screen, they can press fire to skip it, like other players. Because of the way level transition actions are ordered, the server only sends the clients information about the next level once that transition screen expires, so in the remaining situation that the host is in fact at the keyboard and happy to watch the screen display the winners of the most recent game, everyone has to wait for it to finish. This is the one place where the behavior may be possible to improve. However, odds are, there's a lot of room for things breaking if clients enter a level before the server does, so it's a scary portion of the code to mess with, for limited benefit.

I think these explanations make good sense, so thanks for these. It turns out the concerns Shaker raised about /idleserver weren't really valid and aren't actually related to idleserver.

If idleserver uses neglible amounts of resources, then joining your own server as client to watch other clients will net the same thing and be just as effective.

And idleserver giving 10ms has been debunked here too thanks to minmay, because it apparently is related to minimizing your game, not to idleserver.

I vouch to implement cooba's suggestion of not drawing any layers at all when in idleserver mode (just text and a black screen) to further push on it's purpose and low CPU usage. It would also be nice if Shaker starts using idleserver now for the sake of hiding those numbers in the listservers.