3 ms·
My current wait % on the global lock is 0.02%. Deletes and updates will yield. Inserts won't, but the insert happen to memory, which is fast. I think disk satur
by latch 15y ago
My current wait % on the global lock is 0.02%. Deletes and updates will yield. Inserts won't, but the insert happen to memory, which is fast. I think disk saturation on long sync delays is really the only major pain point now (and even that seems better than it used to be)
- rbranson 15y agoThe problem is: "a pending write lock acquisition will prevent further read lock acquisitions until fulfilled." Inserts aren't actually guaranteed to be in memory, as they're done in a file-backed memory region. A write and page fault can and frequently does cause a flush and hang while that lock is held, particularly as the hot dataset size increases relative to physical RAM.