Now Apache2 has 5 dedicated processes for Keystone Admin and 5 for
Keystone Public. As each Apache process consumes some memory and
we arbitrarly decided 5 was a good number more than 2 years ago,
maybe now (with the recent memory pressure we feel) is a good time
to reconcider.
With 5 processes our peakmem_tracker.py script reports a max RSS size
for the "wsgi:keystone-ad" and "wsgi:keystone-pu" processes of
2 (public and admin) * 5 (number of processes) * 90 Mo (RSS of each
process) = 900 Mo.
With 3 processes, the overall max RSS for Keystone is
2 * 3 * 90 = 540 Mo.
Note that this is RSS memory, but using the "smem" linux command on
my laptop, I noticed that the USS (Unique set size, i.e RSS excluding
shared memory) is around 80Mo per process. So reducing the number of
processes will actually reduce memory consumption.
Change-Id: Iba72d94aa15ecaa87c0115ad26d6bpeakmem_tracker62d5b3bea0a
fe1d3d6a7b