vedderb
Real-time data performance mods
VESC-Tool would consume >70% processor while idle, but receiving real-time data.
These changes address the vast bulk of the idle processor load. I see only around 12% idle, for a reduction of over 80%.
Note, however, that while viewing the real-time graph processor load is still extremely high.
is this still relevant? or ready to merge?
Since it's Qt 5.15 behavior on macOS, it is still relevant to macOS. It might be a resolved problem on Qt 6.x, but last I heard from @vedderb's he intends to keep with Qt 5.15 in response to the Qt Corp's nastiness regarding licensing with Qt 6..
I think we talked about this on the discord back then. I also added some improvements since that greatly increased the performance on slow computers. This does a bit more, but the drawback is that when you leave a rt data page while sampling and go back to it the data that arrived in that time will be missing, which is why I didn't want to include this pr.
I just tried it now, and when I sample RT, IMU, APP and BMS data at the same time and have the plot open on fullscreen VESC Tool draws about 1% of my total CPU (25-40% on one of the cores at worst). When the plot page is not open and sampling is active that core goes down to almost nothing.
We did, here's the link to that convo: https://discord.com/channels/904830990319485030/910253910655123566/937017928417685506
Quoting from that link:
changes ... pushed to
masterwere a nice... upgrade... but even with those in place my CPU idle load hardly dropped (72%-->69%)... Whereas with this PR I see the processor load drop to 12-15%.
IIRC, you use Linux and thus the Qt subsystem idles substantially better for you than for macOS users. I don't think we ever discovered why Qt 5 behaves that way, but I know this problematic Qt CPU usage affects many more Qt 5 applications than just VESC-Tool.
I also don't remember us finding a better solution than this PR to address the CPU issues on macOS, so to answer @Teslafly's question the PR is still relevant to a subset of VESC-Tool users. That doesn't preclude closing it, since if it's never going to get merged it doesn't make sense to leave it lingering open. The problem and work-around are documented here, so macOS users who roll their own VESC-Tool can use this code.