Hey there! I've been running several (6) minecraft servers for like 2 months, here they are: S1 Freebuild, 5 maps (main map 2000x2000, lobby 150x150, survival 200x200, freebuild 1000x1000, nether 500x500), all maps are under 300mb, some of them are even 17mb. The most strange thing about this one is that on 50 online it runs bloody smooth, when sometimes it can start hanging up on 10-15 players. S2 Survival, 3 maps (main map 2000x2000, nether 500x500, map for resources 500x500), main map is 300mb, nether is 21mb, resources map 37mb Players online about 30-40, no lags then, only when the player rate is below 10 (yeah, lol.) S3 Roleplay, 2 maps (main map 2000x2000, nether 500x500), main map is 96mb, when nether weights 9mb. It's the most lagged server of all times, propably beacuse of levelcraft, but I'm not sure about this. Online - about 15-20 per day. Can be laggy even when 1 online. Sometimes it's just unplayable S4 Freebuild, just for one of the popular Polish community reddit-like site. Started to lag recently. Main map is 500mb, Freebuild flat map is 20mb, nether 40mb, survival 40mb. Not sure about the maps dimensions but they shouldn't be too big. S4-dev Small server that is building new map for S4. I tought I'll mention about it here too. Maps - 40mb for main map, 28mb for flatlands, 39mb sv. S5 Another freebuild, i tought I'll host them beacuse of nice and friendly administration. Two small maps - first is 230mb, second, nether - 15mb. Not sure about the dimensions aswell S6 MCForge server, takes like nothing CPU even on 40 online players.. I tried to fix it by changing the start line, it's somehow better, but still laggy. CPU goes to 100% sometimes, but only on single thread - the whole CPU is on about 30-40%. All servers are running on the same machine, all of them use the same startup script: What can I do to minimalize lags? Throw out some plugins/change the startup script/use taskset?
@Rabus It's likely that you've simply maxed out the CPU's capacity with 6 servers running. I would recommend a max of 3 servers on a quad core machine, so that each core has a server and one core for all the misc other tasks. But if it hasn't been laggy until now, I'm not sure why it would start now. Did you upgrade to build 1060? Do you use CraftProxy to connect them together? (Cool I'm not the only one who runs more than 4 servers )
Hmmm....CB build 1060 introduces some new multithreaded stuff that could be causing your problems (or helping a little bit..). I'm not sure how the CPU would handle bukkit being multithreaded AND having 7 servers up. Have you noticed if the lag happens when there are players on more than 1-2 of the servers at the same time? What I think might be happening is that because you have 7 servers up (even a small dev server DOES take up a lot of resources CPU wise), it's putting 2 in each physical core. When two of them that are in the same core BOTH have players on them, they both experience lag. The core distribution is probably based off of the order that they were booted up in. Is there any way that you could provide the full log for all of them over pastebin, I'd like to go in and make a quick line graph and see whether or not there are players on more than one server when the lag starts.
All I could tell you that lags can occur even when the total online is 20-25, and it'll be lag-free with total 150 online. So it's completly random... But okay, I'll upload logs somewhere in a sec
@Rabus Okay, I also noticed that you have BigBrother on some of your servers. How are the databases stored? (H2 or MySQL, Same machine or dedicated database server) Also, I'm about to try to get some sleep so I won't be able to check out the logs till tomorrow.
