File lparstat-Fix-negative-values-seen-while-running... of Package powerpc-utils.30280

Overview Repositories Revisions Requests Users Attributes Meta

File lparstat-Fix-negative-values-seen-while-running-lpar.patch of Package powerpc-utils.30280

From 73ba26c1240a25e7699449e82cfc09dad10fed80 Mon Sep 17 00:00:00 2001
From: Sathvika Vasireddy <sv@linux.ibm.com>
Date: Fri, 9 Dec 2022 15:26:46 +0530
Subject: [PATCH 1/3] lparstat: Fix negative values seen while running lparstat
 with -E option

Negative values are seen while running lparstat with -E option.
This is because delta_purr value is less than delta_idle_purr.
Given that these values are read from different sources, a
small variation in the values is possible. So, in such cases,
round down delta_idle_purr to delta_purr.

Without this patch:
=====
System Configuration
type=Dedicated mode=Capped smt=8 lcpu=240 mem=67033290112 kB cpus=0
ent=240.00

---Actual---                 -Normalized-
%busy  %idle   Frequency     %busy  %idle
------ ------  ------------- ------ ------
 -0.03 100.02  3.93GHz[111%]   0.01 110.97
  0.00 100.00  3.93GHz[111%]   0.01 110.99
 -0.04 100.03  3.93GHz[111%]   0.01 110.98
  0.06  99.95  3.93GHz[111%]   0.01 110.99
  0.02  99.98  3.93GHz[111%]   0.01 110.99
=====

With this patch:
=====
System Configuration
type=Dedicated mode=Capped smt=8 lcpu=240 mem=67033290112 kB cpus=0
ent=240.00

---Actual---                 -Normalized-
%busy  %idle   Frequency     %busy  %idle
------ ------  ------------- ------ ------
  0.03  99.96  3.93GHz[111%]   0.01 110.98
  0.00 100.00  3.93GHz[111%]   0.01 110.99
  0.03  99.97  3.93GHz[111%]   0.01 110.99
  0.00 100.00  3.93GHz[111%]   0.01 110.99
  0.09  99.90  3.93GHz[111%]   0.01 110.99
=====

Reported-by: Shirisha Ganta <shirisha.ganta1@ibm.com>
Signed-off-by: Sathvika Vasireddy <sv@linux.ibm.com>
Signed-off-by: Tyrel Datwyler <tyreld@linux.ibm.com>
---
 src/lparstat.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/src/lparstat.c b/src/lparstat.c
index 31a4ee8..eebba1f 100644
--- a/src/lparstat.c
+++ b/src/lparstat.c
@@ -492,6 +492,15 @@ void get_cpu_util_purr(struct sysentry *unused_se, char *buf)
 	delta_purr = get_delta_value("purr");
 	delta_idle_purr = get_delta_value("idle_purr");
 
+	/*
+	 * Given that these values are read from different
+	 * sources (purr from lparcfg and idle_purr from sysfs),
+	 * a small variation in the values is possible.
+	 * In such cases, round down delta_idle_purr to delta_purr.
+	 */
+	if (delta_idle_purr > delta_purr)
+		delta_idle_purr = delta_purr;
+
 	physc = (delta_purr - delta_idle_purr) / delta_tb;
 	physc *= 100.00;
 
@@ -507,6 +516,15 @@ void get_cpu_idle_purr(struct sysentry *unused_se, char *buf)
 	delta_purr = get_delta_value("purr");
 	delta_idle_purr = get_delta_value("idle_purr");
 
+	/*
+	 * Given that these values are read from different
+	 * sources (purr from lparcfg and idle_purr from sysfs),
+	 * a small variation in the values is possible.
+	 * In such cases, round down delta_idle_purr to delta_purr.
+	 */
+	if (delta_idle_purr > delta_purr)
+		delta_idle_purr = delta_purr;
+
 	physc = (delta_purr - delta_idle_purr) / delta_tb;
 	idle = (delta_purr / delta_tb) - physc;
 	idle *= 100.00;
-- 
2.40.1

Places

File lparstat-Fix-negative-values-seen-while-running-lpar.patch of Package powerpc-utils.30280

Places