thinkorswim crashes on Windows 7?


New member
Ever since Sunday 6/14, thinkorswim Desktop app keeps crashing on me. Happens on two PCs, both with Windows 7 (home premium, 64-bit). On Monday and Tuesday, I spent over 4 hours on the phone waiting for TOS specialists. It was an *awesome* use of my time as both specialists blamed my PCs rather than their weekend update... So I hope that someone here may have experience / suggestion. Even if you run TOS on Windows 7 with no interruptions at all, that'd be useful to know... Here are my typical symptoms:

1. After 5-10-15 minutes of TOS working ok, Windows reports on low memory and recommends shutting down TOS. Task Manager shows ~60% memory use (8g machine), which is quite normal and shouldn't cause an issue (screen shot is attached).

2. chromium.exe fails (screen shot is attached), then TOS just simply shuts down. I wasn't aware of this chromium app, but turned out it is part of TOS (apparently they use it for their education tab, which I got disabled by now). BTW - I have chrome browser installed only on one of my PC's.

3. Interestingly, as the day proceeds, TOS becomes more stable. On both Monday and Tuesday, I had to re-launch TOS 7-8 times in first few hours of trading, but since late AM / early PM I was finally able to work almost with no issue. Until this morning of course ;-)



  • Msg.pdf
    198.5 KB · Views: 5

Jack 2

Contacted their team today. They said they're going to fix it, whatever that means


Active member
I think TOS has always been a RAM hog In my case it does not crash but it just runs slow to the point that I click on one of the simulated trades to analyze trade and I have to wait about 30-40 seconds for something to happen
And if you have a browser or other things open it's even worse to the point's frozen and I have to slowly use the task manager to shut things off since it takes a lot longer to go to each program and wait for it to shut down
In my case I use Firefox so I see a lot of Browsercore entries in the Task manager processes running

The only thing they suggested other than getting more ram was to reset the workspace to default which means you will loose all your simulated trades but at least it works normally for a while untill I have too many simulated trades again
Of course during trading hours is even worse because than the prices are updating and keep changing so I imagine the cpu is more active

I can't just add ram to the pc at work so I just have to mudlle through it and manage as best I can
Sometimes if I have too many windows open I can't even start TOS so I have to close all windows than start TOS


TOS interesting discussions will give you a better idea of the issues with TOS

For those of you who don’t have a computer background, Java is the language they use to write TOS. Java Swing is the way that the windows are rendered. Swing is a 2D window library and it is single threaded. If you run a debugger on TOS you can see that the CPU spends the most time drawing the boxes around cells so you will see the biggest performance hit with more watchlists and charts up.

This also means that for the best performance you need to be looking for a CPU with the highest single threaded performance. More cores will basically do nothing to speed up TOS. The naïve way to think about this is to find the highest GHz on the potential computer. Fancy graphic cards also do very little since TOS is CPU bound in the Swing Thread and that is not offloaded to the vector processors.
Last edited:


A possible fix IF you want to take advantage of multi cores CPU's) is to run multiple of the program .

I confirmed with ToS that it is single threaded. And if this is true then having a dual xeon system for thinkorswim will serve no purpose like the guy mentioned above unless you were running multiple instances.

How can I bring up this debugger? I spoke with ToS and they are blaming the issue still on workspace or GPU. But from your post it sounds like it is CPU.

His primary issue is the risk profile and bringing up different structures on simulated and existing trades.


Active member
Good info Tb2018. I used to run two instances of TOS, one for execution and other for anything else. Don't do it anymore.
Another 'trick' to help with Java issues is this: if you run TOS all day long, especially in multiwindow mode, do restart TOS every few hours (depends on your free memory). Java does poor a job on so called 'garbage collection', which means releasing unused memory to system. I use this method sometimes if need to work with more windows than my standard 2. If you wont do this, TOS became very laggish at the EOD.
I guess rewriting code in monster system like TOS ain't that easy... probably it was fine in early days.
Contact Us