19-08-2021, 12:07 AM
(This post was last modified: 19-08-2021, 01:25 AM by timconkling.)
I've been having performance issues with Obi Cloth, and have been spending lots of time in the profiler to get a handle on how to improve things.
I've noticed that Obi allocates quite a lot of memory each frame - in my scene with 6 clothed characters, `ObiLateFixedUpdater` is allocating ~2.5 kb each frame. At least some of this is very easily eliminated.
`ObiUpdater.BeginStep` and `ObiUpdater.Substep` both allocate a new temporary List each time they're called. This list can be moved into a member variable to avoid the repeated allocation:
`ObiSolver.Update` also does some unnecessary allocation, because it calls `Mathf.Max(params float[])`, which allocates a temporary params array. (It also accesses `transform.lossyScale` - which I think involves a roundtrip out of managed code and into the engine - three times). I've made this minor tweak:
These changes bring my allocations down to ~1.5kb per frame, which is a good start - but far from perfect!
I really like Obi, and I'm a bit surprised to see so much `GC.alloc` action every frame. I'd love to be able to do cloth simulation without any allocations... might there be a performance pass done in the future?
Cheers!
I've noticed that Obi allocates quite a lot of memory each frame - in my scene with 6 clothed characters, `ObiLateFixedUpdater` is allocating ~2.5 kb each frame. At least some of this is very easily eliminated.
`ObiUpdater.BeginStep` and `ObiUpdater.Substep` both allocate a new temporary List each time they're called. This list can be moved into a member variable to avoid the repeated allocation:
Code:
private List<IObiJobHandle> m_JobHandles = new List<IObiJobHandle>();
protected void Substep(float stepDeltaTime, float substepDeltaTime, int index)
{
using (m_SubstepPerfMarker.Auto())
{
// Kick off all solver jobs:
foreach (ObiSolver solver in solvers)
if (solver != null)
this.m_JobHandles.Add(solver.Substep(stepDeltaTime, substepDeltaTime, index));
// wait for all solver jobs to complete:
foreach (IObiJobHandle handle in this.m_JobHandles)
if (handle != null)
handle.Complete();
this.m_JobHandles.Clear();
}
}`ObiSolver.Update` also does some unnecessary allocation, because it calls `Mathf.Max(params float[])`, which allocates a temporary params array. (It also accesses `transform.lossyScale` - which I think involves a roundtrip out of managed code and into the engine - three times). I've made this minor tweak:
Code:
void Update()
{
var lossyScale = transform.lossyScale;
m_MaxScale = Mathf.Max(Mathf.Max(lossyScale.x, lossyScale.y), lossyScale.z);
}These changes bring my allocations down to ~1.5kb per frame, which is a good start - but far from perfect!
I really like Obi, and I'm a bit surprised to see so much `GC.alloc` action every frame. I'd love to be able to do cloth simulation without any allocations... might there be a performance pass done in the future?
Cheers!
). Both improvements will be included.