Public bug reported: [Impact]
There is performance overhead observed when many threads are using hugetlbfs in the database environment. [Fix] bdfbd98bc018 hugetlbfs: take read_lock on i_mmap for PMD sharing The patch improves the locking by using the read lock instead of the write lock. And it allows multiple threads searching the suitable shared VMA. As there is no modification inside the searching process. The improvement increases the parallelism and decreases the waiting time of the other threads. [Test] The customer stand-up a database with seed data. Then they have a loading "driver" which makes a bunch of connections that look like user workflows from the database perspective. Finally, the measuring response times improvement can be observed for these "users" as well as various other metrics at the database level. [Regression Potential] The modification is only in replacing the write lock to a read one. And there is no modification inside the loop. The regression probability is low. ** Affects: linux (Ubuntu) Importance: Undecided Assignee: Gavin Guo (mimi0213kimo) Status: New ** Tags: sts -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1882039 Title: The thread level parallelism would be a bottleneck when searching for the shared pmd by using hugetlbfs To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1882039/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs