Fix SystemTap dtrace warning about smgr probe argument types.

Commits ca326e903 and 1f8c504e3 widened the byte-count arguments of
smgr__md__read__done and smgr__md__write__done to "long long int".
SystemTap's dtrace(1) fails on that specific spelling and falls back
with a warning (misreported near the previous probe).  Use ssize_t
and size_t instead, matching the md.c call sites.

Revise probes.d's note about which types are usable as probe
arguments: recommend using system-supplied type names (macOS dtrace
rejects names like PostgreSQL's uint64), and call out "long long int"
as a known SystemTap failure case rather than a wider failure mode.

Also, update the monitoring.sgml entries for these probes,
which were missed by the prior commits.

Reported-by: Laurenz Albe <[email protected]>
Author: Andrey Rachitskiy <[email protected]>
Reviewed-by: Tom Lane <[email protected]>
Discussion: 
https://postgr.es/m/[email protected]

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/8f191a79617d906e34d041382e6ecfbf78166a65

Modified Files
--------------
doc/src/sgml/monitoring.sgml |  4 ++--
src/backend/utils/probes.d   | 14 ++++++++++----
2 files changed, 12 insertions(+), 6 deletions(-)

Reply via email to