Fix number of iterations in spin-loops in case if #cpus < #threads #284
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Signed-off-by: Evgeniy Moiseenko <[email protected]>
Signed-off-by: Evgeniy Moiseenko <[email protected]>
Signed-off-by: Evgeniy Moiseenko <[email protected]>
Signed-off-by: Evgeniy Moiseenko <[email protected]>
Signed-off-by: Evgeniy Moiseenko <[email protected]>
Signed-off-by: Evgeniy Moiseenko <[email protected]>
Signed-off-by: Evgeniy Moiseenko <[email protected]>
Signed-off-by: Evgeniy Moiseenko <[email protected]>
Signed-off-by: Evgeniy Moiseenko <[email protected]>
Signed-off-by: Evgeniy Moiseenko <[email protected]>
Signed-off-by: Evgeniy Moiseenko <[email protected]>
Signed-off-by: Evgeniy Moiseenko <[email protected]>
Signed-off-by: Evgeniy Moiseenko <[email protected]>
ndkoval
requested changes
Mar 2, 2024
src/jvm/test/org/jetbrains/kotlinx/lincheck_test/AbstractLincheckTest.kt
Outdated
Show resolved
Hide resolved
src/jvm/test/org/jetbrains/kotlinx/lincheck_test/AbstractLincheckTest.kt
Outdated
Show resolved
Hide resolved
src/jvm/main/org/jetbrains/kotlinx/lincheck/runner/FixedActiveThreadsExecutor.kt
Outdated
Show resolved
Hide resolved
Signed-off-by: Evgeniy Moiseenko <[email protected]>
Signed-off-by: Evgeniy Moiseenko <[email protected]>
Signed-off-by: Evgeniy Moiseenko <[email protected]>
Signed-off-by: Evgeniy Moiseenko <[email protected]>
…utor Signed-off-by: Evgeniy Moiseenko <[email protected]>
Signed-off-by: Evgeniy Moiseenko <[email protected]>
ndkoval
requested changes
Mar 4, 2024
src/jvm/main/org/jetbrains/kotlinx/lincheck/runner/FixedActiveThreadsExecutor.kt
Show resolved
Hide resolved
src/jvm/main/org/jetbrains/kotlinx/lincheck/runner/FixedActiveThreadsExecutor.kt
Outdated
Show resolved
Hide resolved
src/jvm/main/org/jetbrains/kotlinx/lincheck/runner/FixedActiveThreadsExecutor.kt
Outdated
Show resolved
Hide resolved
src/jvm/main/org/jetbrains/kotlinx/lincheck/runner/FixedActiveThreadsExecutor.kt
Outdated
Show resolved
Hide resolved
|
@eupp please investigate why builds on Teamcity take longer and fail periodically with this change. |
|
The fails are due to #286 |
|
As for the performance degradation, it does not look like this is a stable performance degradation. For example, I just re-run Java 17 builds on master, develop and fix-spin-loops branches, and here are results:
If we take last 6 builds of develop (starting from the last branch-off from master), the build time varies from 13m to 20m. |
Signed-off-by: Evgeniy Moiseenko <[email protected]>
ndkoval
approved these changes
Mar 7, 2024
| if (suddenInvocationResult != null) throw ForcibleExecutionFinishError | ||
| if (++i % SPINNING_LOOP_ITERATIONS_BEFORE_YIELD == 0) Thread.yield() | ||
| if (suddenInvocationResult != null) | ||
| throw ForcibleExecutionFinishError |
There was a problem hiding this comment.
please put throw on the same line
|
@eupp I've approved the PR. Please fix the minor issue and merge it. |
Signed-off-by: Evgeniy Moiseenko <[email protected]>
|
Apparently, I cannot merge this until all CI checks are passed : ) |
|
Oh, nevermind, I have just by-passed this problem. |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Currently, Lincheck performs extremely slow on the machines where number of CPUs is less than a number of threads in the tested scenario.
The reason for that is because there are several places in the Lincheck codebase where spin-loops are used to wait for a certain condition. These loops spin a fixed (large) number of times. But if there are no available CPUs, then these spin-loops just consume all the available computational resources and the test hangs.
Previously, only in one of the places where spin-loops are utilized there was implemented a special check for the case when
#cpus < #threads. Because of code duplication, other similar places were omitted by mistake.To address this issue, I extracted common spin-looping logic into an utility class
Spinner(inspired by the similar solutions in the Rust's crossbeam and parking-lot libraries).This class also has a special handling for the case when
#cpus < #threadsto avoid redundant spinning.In future, we might consider to improve the performance of the spinning by utilizing the exponential backoff strategy, similarly as how it is done in the crossbeam library.
Closes #280