PAGEIOLATCH_KP is a wait for a Keep (KP) mode latch on a buffer page that is currently part of an I/O request. Keep mode pins the page against destruction while the I/O is in flight, and since KP conflicts only with Destroy mode, actual waits require an improbable collision.
It rounds out the PAGEIOLATCH_* family for mode completeness.
Is It a Problem?
Effectively never; expect zero. The I/O latch family’s diagnostic weight sits entirely with PAGEIOLATCH_SH (pages being read for queries) and PAGEIOLATCH_EX/UP (pages in write-side I/O), whose average durations expose slow storage.
If the whole family is elevated because the disk subsystem is struggling, this entry might show a trace; it adds nothing the big siblings have not already said.
Common Causes
- Rare pin-versus-teardown collisions on pages in flight.
- A globally slow I/O subsystem inflating everything marginally.
What To Do
- Nothing for this mode.
- For I/O latch analysis, measure
sys.dm_io_virtual_file_statslatency and follow thePAGEIOLATCH_SHplaybook.
How To See It
Rank waits with Get-WaitStatistics; the family’s SH and EX members carry the signal.
If PAGEIOLATCH_KP is sitting near the top of your wait stats, these are the next places to look.
- The waits that usually matter, ranked, with what each one is telling you.
- PAGEIOLATCH_SH Wait Type, the closest wait worth investigating when this one is high.
- Storage & Capacity, the scripts and guides for this part of the stack.
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