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From: Clark Williams <>
Subject: [PATCH] pi_stress: limit the number of inversion groups to the number of online cores
Date: Tue, 21 Jul 2020 16:10:22 -0500
Message-ID: <> (raw)

Each inversion group is three SCHED_FIFO threads, so the chances of more groups
than online cores actually getting to run is very slim. Limit the number of
groups requested to be <= the number of online cpus.

Signed-off-by: Clark Williams <>
 src/pi_tests/pi_stress.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/pi_tests/pi_stress.c b/src/pi_tests/pi_stress.c
index 0ed844c636cd..ce446d4ea037 100644
--- a/src/pi_tests/pi_stress.c
+++ b/src/pi_tests/pi_stress.c
@@ -1327,6 +1327,12 @@ void process_command_line(int argc, char **argv)
 		case 'g':
 			ngroups = strtol(optarg, NULL, 10);
+			if (ngroups > num_processors) {
+				pi_error("the number of groups cannot exceed "
+					 "the number of online processors (%d)\n",
+					 num_processors);
+				exit(-1);
+			}
 			pi_info("number of groups set to %d\n", ngroups);
 		case 'r':

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Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-07-21 21:10 Clark Williams [this message]
2020-07-21 22:29 ` John Kacur

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