PAGELATCH_KP is a wait for a Keep (KP) mode latch on a data file page in memory (not in an I/O request). Keep mode pins a page so it cannot be destroyed while the holder examines it, and it is compatible with every other latch mode except Destroy. A wait therefore requires the narrow collision of a pin request against an in-progress buffer teardown.
Like the other KP/NL/DT entries, it exists mainly for mode completeness.
Is It a Problem?
No; expect it at or near zero everywhere. The engine’s page latching pain always presents through the working modes: PAGELATCH_SH (read), PAGELATCH_UP (update, allocation bitmaps), and PAGELATCH_EX (modify), with tempdb contention as the classic driver.
If you arrived here from a wait ranking showing meaningful PAGELATCH_KP, double-check the tooling; that would be extraordinary.
Common Causes
- Momentary pin-versus-teardown collisions in the buffer pool.
What To Do
- Nothing for this mode.
- For actual page latch contention, get the
db:file:pagefromsys.dm_os_waiting_tasksunder the real modes and follow the tempdb/hot-page playbooks.
How To See It
Rank waits with Get-WaitStatistics; the working modes carry any real page latch story.
PAGELATCH_KP is background noise on a healthy instance. If you are chasing a real problem, start with the waits that actually cost you time.
- The waits that usually matter, ranked, with what each one is telling you.
- PAGELATCH_EX Wait Type, the closest wait worth investigating when this one is high.
- Performance & Troubleshooting, the scripts and guides for this part of the stack.
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