Fixes https://github.com/pytorch/torchtitan/issues/1185
It looks like inductor's logic to include inductor configs in the cache key skips configs with a leading underscore by default. This came up in torchtitan - there's an asyncTP pipelining pass in inductor gated by a private config, and by not caching on the config we were attempting to use asyncTP when we shouldn't be.
I'm not sure how worried we should be on the blast radius of this change. On the one hand:
(1) it technically fixes any silent correctness issues in the cache around any other private inductor configs (it looks like there are a few)
(2) there is some risk that there are some "harmless" configs that we are now including in the key, which may increase false negatives. I do see that there is an explicit list for "configs we want to ignore for caching" (`_save_config_ignore`), so my hope is that all harmless configs are already encapsulated there.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/153672
Approved by: https://github.com/oulgen
Some functions have empty linemaps, and if you call `PyCodeCache.stack_frames_for_code` on code in the wrong order, you'll end up triggering a too many values to unpack issue: https://github.com/pytorch/pytorch/issues/154536
Specifically, if you populate PyCodeCache's linemap via caching, and then request the stack frames of a inductor generated output file that has an empty linemap, this function will try to unpack too many arguments.
Test plan:
```
import os
os.environ["TORCHINDUCTOR_FX_GRAPH_CACHE"] = "1"
os.environ["TORCHINDUCTOR_AUTOGRAD_CACHE"] = "1"
import torch
@torch.compile
def fn(x: torch.Tensor):
(x_grad,) = torch.autograd.grad(x.sum(), x)
return x_grad
x = torch.randn(10, 10, requires_grad=True)
result = fn(x)
```
Run this twice and see that everything works as expected.
It's hard to exactly pinpoint a good unit test for this: it requires a whole lot of moving parts to get the issue to trigger because:
- The callsite in question in dynamo, without caching, will always run before generating the code, so cls.linemaps[path] will be None most of the time
- The inductor generated output needs to call *back* into dynamo via `assert_size_stride`
- In our test case, the CompiledBackward needs to not have linemaps, and also be called in the middle of a graph break while compiling a different cached function. Caching switches the order the PyCodeCache.linemap is populated (i.e. either before or after the graph break is evaluated), which causes the issue.
All these things need to interact together to create the bug, so it's a bit difficult to write a simple unit test.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/155064
Approved by: https://github.com/bdhirsh
For graph partition, `write_get_raw_stream_header_once` is done once so the autotune code may not have the header. This PR additionally calls `write_get_raw_stream_header` in `codegen_device_guard_enter` before `get_raw_stream` is used.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/154698
Approved by: https://github.com/oulgen
Triton has added another artifact that gets generated (triton-lang/triton#6992), so `test_cache_load_function` started failing as there are now 8 (instead of 7) artifacts.
Instead of figuring out a way to check exactly which set of artifacts will get generated, I instead modified the test to just check that there are _at least_ 6 artifacts, to account for different platforms (intel/amd/nvidia) and different triton versions (which may or may not have a `.source` artifact)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/154879
Approved by: https://github.com/oulgen, https://github.com/masnesral
Fixes https://github.com/pytorch/torchtitan/issues/1185
It looks like inductor's logic to include inductor configs in the cache key skips configs with a leading underscore by default. This came up in torchtitan - there's an asyncTP pipelining pass in inductor gated by a private config, and by not caching on the config we were attempting to use asyncTP when we shouldn't be.
I'm not sure how worried we should be on the blast radius of this change. On the one hand:
(1) it technically fixes any silent correctness issues in the cache around any other private inductor configs (it looks like there are a few)
(2) there is some risk that there are some "harmless" configs that we are now including in the key, which may increase false negatives. I do see that there is an explicit list for "configs we want to ignore for caching" (`_save_config_ignore`), so my hope is that all harmless configs are already encapsulated there.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/153672
Approved by: https://github.com/oulgen
ghstack dependencies: #153766
https://github.com/pytorch/pytorch/pull/152708 expanded support of `get_estimated_runtime` to many more types of `SchedulerNodes`. This caused an increase in compile time because we're always calling `get_estimated_runtime` to populate the metrics table. This PR adds a flag for this logging, which reduces the instruction count by 8%. Long term, we should probably merge metrics.py with TORCH_LOGS/tlparse (suggestion from @xmfan).
Update: added support for TORCH_LOGS for the metrics logging.
Test Plan:
mm_loop.py and many existing tests cover.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/153506
Approved by: https://github.com/eellison
When loading statically launchable triton kernels from FxGraphCache, since we don't instantiate a CachingAutotuner like we do normally, we need to recheck the autotune cache based on the existing compile results. If we get a hit, we take the compile result whose config matches the best config.
Sometimes, the best config will have been from coordinate descent tuning. In this case, FxGraphCache today does not cache the resulting triton kernel, neither with static or without static cuda launcher. This is because coordinate descent tuning happens at runtime, and if the best config happens to not be one of the precompiled configs.
Test Plan:
New unit test that failed before
Pull Request resolved: https://github.com/pytorch/pytorch/pull/153565
Approved by: https://github.com/aorenste
When loading statically launchable triton kernels from FxGraphCache, since we don't instantiate a CachingAutotuner like we do normally, we need to recheck the autotune cache based on the existing compile results. If we get a hit, we take the compile result whose config matches the best config.
Sometimes, the best config will have been from coordinate descent tuning. In this case, FxGraphCache today does not cache the resulting triton kernel, neither with static or without static cuda launcher. This is because coordinate descent tuning happens at runtime, and if the best config happens to not be one of the precompiled configs.
Test Plan:
New unit test that failed before
Pull Request resolved: https://github.com/pytorch/pytorch/pull/153565
Approved by: https://github.com/aorenste
Today, we mark graph outputs as maybe dynamic, this lets a compilation to communicate to future compilations whether certain graph inputs are dynamic. Similarly, we can do this to saved activations, which may be used in future compilations as well. This is especially prevalent in compiled autograd, where tensor activations will always become graph inputs.
Changes to the tests were mainly cosmetic, with the exception of tests that relied on duck shaping. By annotating tensor dims, we prevent them from reusing pre-existing symbols, so this change will make graphs use duck shapes less than before, which affects some of the caching tests.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/149707
Approved by: https://github.com/bdhirsh
standalone_compile needs to get dynamic shape information from
somewhere. We add a new `dynamic_shapes` argument with three options:
1. from the passed-in graph (dynamic="from_graph"). This is the default.
2. from the example inputs, thereby specializing on them. (dynamic="from_example_inputs")
3. from the current tracing context (dynamic="from_tracing_context")
1 and 3 are not exactly the same. 2 can also be used for more advanced
things... (specialize on one input but not the other).
Most of this PR is tests.
Test Plan:
- a lot of new tests.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/151788
Approved by: https://github.com/oulgen
This PR fixes two things.
The first problem is that in the vLLM style standalone_compile is
called from within a custom torch.compile backend. If there already is a
FakeTensorMode (which there is), we shouldn't create a new
FakeTensorMode with the same shape_env, instead we should just reuse the
same FakeTensorMode.
The second thing is that compile_fx can mutate the passed in gm, so we
deepcopy (since standalone_compile should be standalone)
Test Plan:
- new test
- updated old tests
Pull Request resolved: https://github.com/pytorch/pytorch/pull/151502
Approved by: https://github.com/oulgen
ghstack dependencies: #151501, #151551
We were only returning the first one. There's an edge case on what to do
if the original function returns a single Tensor. capture(f) returns a
function that returns a tuple of one Tensor in this case and we were
originally converting this back to one single Tensor. I think it's fine
to return a tuple of one Tensor (that is what the graph passed to
standalone_compile asked for!) but we can revisit.
fine
Test Plan:
- modified one test to used multiple outputs
Pull Request resolved: https://github.com/pytorch/pytorch/pull/151551
Approved by: https://github.com/Skylion007, https://github.com/oulgen
ghstack dependencies: #151501
This PR adds standalone_compile API that does precompilation via caching to support vLLM use case in the short term while we work on the longer term precompilation solution.
```
standalone_compile(gm, example_inputs, options) -> CompiledArtifact
CompiledArtifact.save(path, format: binary|unpacked = binary)
CompiledArtifact.load(path, format: binary|unpacked = binary)
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/150670
Approved by: https://github.com/jamesjwu, https://github.com/zou3519
This PR adds standalone_compile API that does precompilation via caching to support vLLM use case in the short term while we work on the longer term precompilation solution.
```
standalone_compile(gm, example_inputs, options) -> CompiledArtifact
CompiledArtifact.save(path, format: binary|unpacked = binary)
CompiledArtifact.load(path, format: binary|unpacked = binary)
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/150670
Approved by: https://github.com/jamesjwu, https://github.com/zou3519
This PR adds standalone_compile API that does precompilation via caching to support vLLM use case in the short term while we work on the longer term precompilation solution.
```
standalone_compile(gm, example_inputs, options) -> CompiledArtifact
CompiledArtifact.save(path, format: binary|unpacked = binary)
CompiledArtifact.load(path, format: binary|unpacked = binary)
```
Pull Request resolved: https://github.com/pytorch/pytorch/pull/150670
Approved by: https://github.com/jamesjwu, https://github.com/zou3519
Summary:
**Context**: https://github.com/pytorch/pytorch/pull/150122 (D71982587 - let's call this "the WS diff") introduces "bc/fc-breaking" cache changes.
In particular, it introduces `num_consumer_groups` and adds it to the cached config. In versions of torch that include the WS diff, `num_consumer_groups` is treated as a class variable on a triton.Config object (i.e. `triton.Config({..kwargs..}, num_consumer_groups=num_consumer_groups, ...`). And in versions of torch that don't include the WS diff, you generally don't expect to see this kwarg.
But if a program is run WS-torch (i.e. torch w/ the WS diff), and then later you run the same program with non-WS-torch, then non-WS-torch is going to find this autotune cache entry, and interpret `num_consumer_groups` as a kwarg, because there's no special handling for for num_consumer_groups in this version of torch. Then the program crashes with a triton failure message.
**The fix**: add the torch version / torch key into the hash, so that any changes to inductor will invalidate the cache (ensuring that other changes to triton_heuristics won't cause these bc/fc issues).
Test Plan: D72285868 (or https://gist.github.com/davidberard98/2ea697eb550c94d0d1948fedb5c5c7d8, but this doesn't repro in OSS because this version of warp specialization is not available in oss triton) can repro the failure, and the failure is fixed after this PR is patched.
Also, added a test in test/inductor/test_codecache.py which verifies that there's no cache hit if the torch_key changes (and verified that without the functional changes in this PR, the test fails).
Differential Revision: D72285303
Pull Request resolved: https://github.com/pytorch/pytorch/pull/150494
Approved by: https://github.com/oulgen
This PR adds CachingAutotuners that are statically launchable to FXGraphCache's cache entry.
Regular CachingAutotuners, with triton kernels attached to them, are not very good to cache: they are very large, and take huge amounts of space since they track all of the various binary files, along with various metadata. We could probably figure out what information we could delete from the kernel and have it still work, but with StaticCudaLauncher, we no longer have to. Instead, we can cache every compiled triton kernel that is statically launchable.
Because StaticTritonCompileResult is serializable, and designed to have a very small memory footprint, we can save it into FXGraphCache without increasing the cache size significantly. We store it as a part of CompiledFxGraph.triton_bundle.
Then, on load, we repopulate the CachingAutotuner into our CompiledTritonKernel cache.
The upsides of this are many:
- We no longer need to call into a separate process on cache hit
- We can *guarantee* that the triton kernel we got from our cache entry is the one we use to launch again, so no worries about triton's own caching logic
- Once we achieve feature parity and all torch.compiled triton kernels are statically launchable, we can clean up a bunch of TritonBundler code and simplify the cache hit logic.
Fixes#149449
Pull Request resolved: https://github.com/pytorch/pytorch/pull/149054
Approved by: https://github.com/oulgen
This PR adds CachingAutotuners that are statically launchable to FXGraphCache's cache entry.
Regular CachingAutotuners, with triton kernels attached to them, are not very good to cache: they are very large, and take huge amounts of space since they track all of the various binary files, along with various metadata. We could probably figure out what information we could delete from the kernel and have it still work, but with StaticCudaLauncher, we no longer have to. Instead, we can cache every compiled triton kernel that is statically launchable.
Because StaticTritonCompileResult is serializable, and designed to have a very small memory footprint, we can save it into FXGraphCache without increasing the cache size significantly. We store it as a part of CompiledFxGraph.triton_bundle.
Then, on load, we repopulate the CachingAutotuner into our CompiledTritonKernel cache.
The upsides of this are many:
- We no longer need to call into a separate process on cache hit
- We can *guarantee* that the triton kernel we got from our cache entry is the one we use to launch again, so no worries about triton's own caching logic
- Once we achieve feature parity and all torch.compiled triton kernels are statically launchable, we can clean up a bunch of TritonBundler code and simplify the cache hit logic.
Fixes#149449
Pull Request resolved: https://github.com/pytorch/pytorch/pull/149054
Approved by: https://github.com/oulgen
This PR adds CachingAutotuners that are statically launchable to FXGraphCache's cache entry.
Regular CachingAutotuners, with triton kernels attached to them, are not very good to cache: they are very large, and take huge amounts of space since they track all of the various binary files, along with various metadata. We could probably figure out what information we could delete from the kernel and have it still work, but with StaticCudaLauncher, we no longer have to. Instead, we can cache every compiled triton kernel that is statically launchable.
Because StaticTritonCompileResult is serializable, and designed to have a very small memory footprint, we can save it into FXGraphCache without increasing the cache size significantly. We store it as a part of CompiledFxGraph.triton_bundle.
Then, on load, we repopulate the CachingAutotuner into our CompiledTritonKernel cache.
The upsides of this are many:
- We no longer need to call into a separate process on cache hit
- We can *guarantee* that the triton kernel we got from our cache entry is the one we use to launch again, so no worries about triton's own caching logic
- Once we achieve feature parity and all torch.compiled triton kernels are statically launchable, we can clean up a bunch of TritonBundler code and simplify the cache hit logic.
Fixes#149449
Pull Request resolved: https://github.com/pytorch/pytorch/pull/149054
Approved by: https://github.com/oulgen
ghstack dependencies: #149657
While using save_cache_artifacts on internal workloads, we have noticed that repeatedly calling this function after every batch is incredibly expensive. This PR significantly speeds up this function call by opting out of pickle and redesigning serialization algorithm.
Essentially what we want is to be able to call serialize many times without incurring costs from scratch.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/148227
Approved by: https://github.com/jamesjwu
ghstack dependencies: #148226
This PR intends to fix the cache related issues from https://github.com/pytorch/pytorch/issues/147405.
It does *not* handle the dynamo recompile case in process, because it does not introduce any extra guards. For FXGraphCache and AOTAutogradCache, we simply have to have the device context in the cache key.
Note that for any function that accepts tensor inputs, the device context is naturally already included in the cache key by the metadata of example inputs. However, for functions that return constants or have no arguments, the device context still needs to be in the cache key.
A more robust fix for this would be to have inductor generate device guards that are dynamic, instead of specialized. This would also help us share more cache artifacts.
I've added unit tests for FXGraphCache and AOTAutogradCache, both of which would fail without this change.
Differential Revision: [D69875939](https://our.internmc.facebook.com/intern/diff/D69875939)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/147464
Approved by: https://github.com/bdhirsh, https://github.com/anijain2305
### Big idea
This PR extends https://github.com/pytorch/pytorch/pull/144288 by combining calling triton in worker processes with the future cache: we kick off triton compilation in the worker processes earlier, during inductor codegen. Basically instead of calling async_compile.triton for the first time only after the entire code has been generated, we start compiling as soon as we know we'll need to compile the kernel. Then, when loading the generated inductor code, we can simply read from our in memory future cache, considerably increasing the parallelism.
### Implementation Overview
In total, the diff does the following:
- Converts TritonFuture to LambdaFuture, only calling triton.compile on worker processes
- Now that triton.compile() isn't called on the main process, we call TritonBundler on all compiled kernels when we get them back from workers
- Extend @eellison's future cache to a class, mostly as a refactor
- Finally, call async_compile.triton ahead of time in Scheduler.codegen if workers are warmed up. This causes the subsequent
async_compile.triton call that occurs after codegen to cache hit on cold start.
In the diffs after this, I will add more to CompiledTritonKernels so that TritonBundler, on a warm start, automatically populates the in memory cache on warm start with the existing triton kernels, avoiding calling triton altogether on warm starts.
Because LambdaFutures are much faster to kick off than TritonFutures, due to not needing to load from TritonCodeCache at all, the time spent kicking off these worker jobs is pretty minimal for inductor codegen.
Differential Revision: [D69123174](https://our.internmc.facebook.com/intern/diff/D69123174/)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/146417
Approved by: https://github.com/jansel
Summary: The current implementation introduces a compile-time regression due to overhead hashing large constants. To support freezing+caching, we consider only the tensor metadata of frozen params, but we neglect to do the same for any constants created as a result of folding frozen params. This PR Explicitly marks the constants created during freezing (and constant folding during freezing) and uses that info in the inductor cache to determine when to hash a tensor value+metadata vs. metadata only.
Test Plan: `python benchmarks/dynamo/torchbench.py --backend inductor --device cuda --only alexnet --bfloat16 --cold-start-latency --print-compilation-time --inference --performance --freezing`
Pull Request resolved: https://github.com/pytorch/pytorch/pull/145868
Approved by: https://github.com/eellison
When we attempt prologue or epilogue fusion with a TritonTemplate, we benchmark it at compile time in order to determine profitability. This avoids slowdowns/register spilling, and allows us to pick fusion when a base triton template is slower than cublas but faster when considering an epilogue. However, that fused benchmarking does not do the same async compilation as we do for the base TritonTemplate. The Base TritonTemplate is async compiled during lowering, then later waited on and benchmarked.
This PR extends a similar process to benchmarking fused TritonTemplates in the scheduler. We keep a list of pending fusions which have async compilations. And we resolve any pending fusions a node is in prior to attempting to fuse it with any other node.
Initially, I saw some slowdowns with this because we kick off async compilations of identical fusions in parallel. To address this I added source code caching at the `async_compile` level (we also already cache benchmark runs, but that would not happen in parallel).
Compilation speedups:
<img width="717" alt="image" src="https://github.com/user-attachments/assets/8e8f7d6c-7824-4210-83f9-a2a0f6db5ac9" />
This also should let us be a bit more aggressive with either configs, or benchmarking other fusions which are hard to determine profitability of.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/143408
Approved by: https://github.com/jansel, https://github.com/shunting314
Summary: In https://github.com/pytorch/pytorch/pull/143563 we have a report of a problem with the treatment of frozen params in the inductor cache implementation. There seems to be a path where new constants are added in the `GraphLowering`. On a cache hit when we try to find those constant names in the `torch.fx.GraphModule`, they do not exist. The current approach treats all constants differently if the GM has any frozen params. This PR changes the approach to only treat the _frozen_ params specially, but store all other constants in the cache entry (as we do without freezing):
1) When creating a cache entry, store the names of any frozen params, but the values of any other constants.
2) On a cache hit, restore the values of the frozen params by looking up in the current GM.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/143808
Approved by: https://github.com/leslie-fang-intel, https://github.com/eellison