[LTP] [PATCH v2] [RFC] pselect01: Tune thresholds

[Jan Stancek <jstancek@redhat.com>]

----- Original Message -----
> Hi!
> > > I guess that the 50us is included in the 250us already. So what about
> > > adding the line you sugests and decreasing the 250us to 200us?
> > 
> > We can do that, but looking again at  PR_GET_TIMERSLACK, it is supported
> > since 2.6.28, so we'd need to skip older kernels or fall back to a
> > default of 50us.
> 
> Let's sort that out after the release, I will commit v2 as it is, ok?

I'm seeing this test failing a lot now on RHEL6/7 as some cases are
now more strict. 

ppc KVM guest
pselect01.c:131: FAIL: pselect() slept for too long 1006090us, expected 1000000us, threshold 2750

slow x86 bare metal system
pselect01.c:145: INFO: CLOCK_MONOTONIC resolution 1 ns
pselect01.c:86: INFO: pselect() sleeping for 0 secs 1000000 nsec 500 iterations
pselect01.c:118: INFO: Mean sleep time 1237.06 us, expected 1000 us, threshold 251.00
pselect01.c:136: PASS: pselect() slept for 618532us, requested 500000us, treshold 125500
pselect01.c:86: INFO: pselect() sleeping for 0 secs 2000000 nsec 500 iterations
pselect01.c:118: INFO: Mean sleep time 2610.75 us, expected 2000 us, threshold 252.00
pselect01.c:131: FAIL: pselect() slept for too long 1305373us, expected 1000000us, threshold 126000
pselect01.c:86: INFO: pselect() sleeping for 0 secs 10000000 nsec 300 iterations
pselect01.c:118: INFO: Mean sleep time 10590.66 us, expected 10000 us, threshold 260.00
pselect01.c:131: FAIL: pselect() slept for too long 3177198us, expected 3000000us, threshold 78000
pselect01.c:86: INFO: pselect() sleeping for 0 secs 100000000 nsec 1 iterations
pselect01.c:136: PASS: pselect() slept for 100670us, requested 100000us, treshold 1850
pselect01.c:86: INFO: pselect() sleeping for 1 secs 0 nsec 1 iterations
pselect01.c:136: PASS: pselect() slept for 1001063us, requested 1000000us, treshold 2750

x86 kvm guest
pselect01.c:145: INFO: CLOCK_MONOTONIC resolution 1 ns
pselect01.c:86: INFO: pselect() sleeping for 0 secs 1000000 nsec 500 iterations
pselect01.c:118: INFO: Mean sleep time 1251.76 us, expected 1000 us, threshold 251.00
pselect01.c:131: FAIL: pselect() slept for too long 625882us, expected 500000us, threshold 125500
pselect01.c:86: INFO: pselect() sleeping for 0 secs 2000000 nsec 500 iterations
pselect01.c:118: INFO: Mean sleep time 2256.17 us, expected 2000 us, threshold 252.00
pselect01.c:131: FAIL: pselect() slept for too long 1128083us, expected 1000000us, threshold 126000
pselect01.c:86: INFO: pselect() sleeping for 0 secs 10000000 nsec 300 iterations
pselect01.c:118: INFO: Mean sleep time 10257.38 us, expected 10000 us, threshold 260.00
pselect01.c:136: PASS: pselect() slept for 3077214us, requested 3000000us, treshold 78000
pselect01.c:86: INFO: pselect() sleeping for 0 secs 100000000 nsec 1 iterations
pselect01.c:136: PASS: pselect() slept for 100283us, requested 100000us, treshold 1850
pselect01.c:86: INFO: pselect() sleeping for 1 secs 0 nsec 1 iterations
pselect01.c:136: PASS: pselect() slept for 1001068us, requested 1000000us, treshold 2750

Regards,
Jan