-
Notifications
You must be signed in to change notification settings - Fork 91
New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
Improve Symbolic Cholesky performance #1758
base: develop
Are you sure you want to change the base?
Conversation
Constexpr evaluation complexity too high
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
for omp part, does it also show better performance than the previous one?
previous one seems to be much shorter than the current one, so maybe we can keep the old one if it does not give better performance
GKO_REGISTER_OPERATION(forest_from_factor, cholesky::forest_from_factor); | ||
GKO_REGISTER_OPERATION(from_factor, elimination_forest::from_factor); |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
previous name seems to be more descriptive.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
elimination_forest::forest_from_factor seemed unnecessarily verbose
GKO_REGISTER_OPERATION(forest_from_factor, cholesky::forest_from_factor); | ||
GKO_REGISTER_OPERATION(from_factor, elimination_forest::from_factor); |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
same comment
{ | ||
constexpr auto size = 8; | ||
using tree = gko::detail::cartesian_tree<size>; | ||
int values[size]{}; |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
int values[size]{}; | |
int values[size]; |
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
That's a technicality about constructing vs. assigning to uninitialized elements that I wanted to avoid. This kind of initialization is required in constexpr code, which is why I used it here as well.
The OpenMP part is not yet parallelized, and the skeleton tree computation is not enabled by default. |
…ssing) see TODOs for problematic points
This improves the symbolic Cholesky performance by preprocessing the matrix on the GPU with a Minimum Spanning Tree algorithm.
Example rgg_22 from SuiteSparse with METIS nested dissection on H100:
The performance improvements are split between device-host transfer (transferring a spanning tree instead of the full matrix) and the elimination tree computation (operating on a sparser graph)