1. Without patch
# ./cyclictest -S -p fifo -D60s
defaulting realtime priority to 9
# /dev/cpu_dma_latency set to 0us
policy: fifo: loadavg: 0.00 0.01 0.05 1/207 12378
T: 0 (12361) P: 9 I:1000 C: 59993 Min: 1 Act: 1 Avg: 1 Max: 8
T: 1 (12362) P: 9 I:1500 C: 39995 Min: 1 Act: 1 Avg: 1 Max: 9
T: 2 (12363) P: 9 I:2000 C: 29996 Min: 1 Act: 1 Avg: 1 Max: 12
T: 3 (12364) P: 9 I:2500 C: 23997 Min: 1 Act: 1 Avg: 1 Max: 9
T: 4 (12365) P: 9 I:3000 C: 19997 Min: 1 Act: 1 Avg: 1 Max: 6
T: 5 (12366) P: 9 I:3500 C: 17141 Min: 1 Act: 1 Avg: 1 Max: 11
T: 6 (12367) P: 9 I:4000 C: 14998 Min: 0 Act: 1 Avg: 1 Max: 10
T: 7 (12368) P: 9 I:4500 C: 13331 Min: 0 Act: 1 Avg: 1 Max: 6
2. With patch
# ./cyclictest -S -p fifo -D60s
defaulting realtime priority to 9
# /dev/cpu_dma_latency set to 0us
policy: fifo: loadavg: 0.05 0.04 0.05 1/206 12469
T: 0 (12452) P: 9 I:1000 C: 59997 Min: 1 Act: 1 Avg: 1 Max: 3
T: 1 (12453) P: 9 I:1500 C: 39998 Min: 1 Act: 1 Avg: 1 Max: 2
T: 2 (12454) P: 9 I:2000 C: 29998 Min: 1 Act: 1 Avg: 1 Max: 4
T: 3 (12455) P: 9 I:2500 C: 23999 Min: 1 Act: 1 Avg: 1 Max: 4
T: 4 (12456) P: 9 I:3000 C: 19999 Min: 1 Act: 1 Avg: 1 Max: 4
T: 5 (12457) P: 9 I:3500 C: 17142 Min: 1 Act: 1 Avg: 1 Max: 3
T: 6 (12458) P: 9 I:4000 C: 14999 Min: 1 Act: 1 Avg: 1 Max: 2
T: 7 (12459) P: 9 I:4500 C: 13332 Min: 1 Act: 1 Avg: 1 Max: 3
Patch ---
diff --git a/src/cyclictest/cyclictest.c b/src/cyclictest/cyclictest.c
index 34053c5..84a70de 100644
--- a/src/cyclictest/cyclictest.c
+++ b/src/cyclictest/cyclictest.c
@@ -1727,6 +1727,9 @@ static void print_stat(FILE *fp, struct thread_param *par,
int index, int verbos
{
struct thread_stat *stat = par->stats;
+ if ( stat->cycles < 5000)
+ stat->max = 0;
+
if (!verbose) {
if (quiet != 1) {
char *fmt;
---
03.08.2015 20:59, pavel пишет:
# ./cyclictest -S -p fifo
defaulting realtime priority to 9
# /dev/cpu_dma_latency set to 0us
policy: fifo: loadavg: 0.00 0.03 0.05 1/218 4240
T: 0 ( 4174) P: 9 I:1000 C: 430806 Min: 1 Act: 1 Avg: 1 Max: 10
T: 1 ( 4175) P: 9 I:1500 C: 287204 Min: 1 Act: 1 Avg: 1 Max: 6
T: 2 ( 4176) P: 9 I:2000 C: 215403 Min: 1 Act: 2 Avg: 1 Max: 11
T: 3 ( 4177) P: 9 I:2500 C: 172322 Min: 1 Act: 1 Avg: 1 Max: 9
T: 4 ( 4178) P: 9 I:3000 C: 143602 Min: 1 Act: 1 Avg: 1 Max: 10
T: 5 ( 4179) P: 9 I:3500 C: 123087 Min: 1 Act: 1 Avg: 1 Max: 11
T: 6 ( 4180) P: 9 I:4000 C: 107701 Min: 1 Act: 1 Avg: 1 Max: 10
T: 7 ( 4181) P: 9 I:4500 C: 108232 Min: 1 Act: 2 Avg: 1 Max: 11
It possible? 1us latency? o_O
No, your latency is 11us. Max latency is what we care about, not the
average.
By the way, max values appear only at the start, then they are roughly equal to
the average.
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