After desperately trying to find the cause of my persistent lag in Spiral Knights I came across something in the Task Manager that I have never seen until today. It is called conhost.exe. It only starts up when I start spiral knights, but I don't think it ever did that before today. I have researched conhost.exe and it seems to be a legitimate thing as long as it is located in the system32 folder, while potentially being a virus elsewhere. Does anyone know if this process is normal when running spiral knights? Thanks.
conhost.exe?
I would think that, as a command line-associated process, it would only start if you opened a command line, but you never know with Windows.
You could right-click the process, select "Properties", and then check its location if you're suspicious. It should be something similar to "C:\Windows\System32".
It runs when the game runs and stops when I close the game. Sounds normal to me.
You may want to try checking for updated graphics card drivers, disabling vsync, running in fullscreen, making sure you're on a relatively close server, using a wired connection instead of a wireless one (no I don't know which you have) or any combination of those options.
If none of those work, perhaps a new graphics card is in order. Otherwise, I'm not sure what to tell you.
This is more of a general guide to increasing general performance, but:
Java
Having the right versions of Java installed can increase the performance of Java-based games (like Spiral Knights) greatly. Right now the latest stable release of Java is Java 6 Update 30, but the faster and slightly unstable Java 7 Update 2 is available. I've been using Java 7 for a while now and haven't run into any problems, so it isn't too unstable under the right conditions.
If you're the only one who uses your computer and you have a 32-bit operating system: Install Java 7 Update 2 (32-bit) and Java 6 Update 30 (32-bit).
If you're the only one who uses your computer and you have a 64-bit operating system: Install Java 7 Update 2 (64-bit) and Java 6 Update 30 (32-bit).
If multiple people use your computer and you have a 32-bit operating system: Install only Java 6 Update 30 (32-bit).
If multiple people use your computer and you have a 64-bit operating system: Install Java 6 Update 30 (64-bit) and Java 6 Update 30 (32-bit).
Graphics Card Drivers
Installing the latest graphics card drivers ensures your graphics card is working as efficiently as it currently can. Drivers differ from card to card, so I can't tell you exactly which driver you need, but almost all computers come with Intel, NVIDIA, or ATI graphics cards. You can probably find the right driver for your card on one of their websites.
Programs Running in the Background
Not all programs stop after you close them and continue to use valuable RAM. Some, like iTunes, continue to run in the background after starting them and closing them and others start when you boot up your computer. These programs usually display an icon in the system tray (the box to the left of the clock). Personally, I only have my anti-virus program running all the time in Windows, but you may have some other programs you want to keep running all the time. In most cases you can stop these programs by right clicking them and clicking "Exit" or "Quit" and stop them from starting at all from their control panel. Some of the more persistent background programs can only be disabled with msconfig and services.msc, but it's possible to break your computer with those programs, so stay away from them unless you know exactly what you're doing.
Fragmentation
The way Spiral Knights updates can cause its files to become very fragmented. What this means is that its files are split up on your hard drive instead of all together, which slows down both reading and writing. There are many free defragmentation programs available, and there isn't really a "best" one, so I won't point to any in particular. Just know that defragmentation can take hours to finish, so it's best to do it overnight.
And Berserkleon, the FPS decrease in performance from enabling VSync is irrelevant if you have triple buffering enabled and you aren't testing video cards.
I have it too, i usually close them just when they start to relase resources