From 39fe2093254db5d4cd223e7d9c228689ba6382ca Mon Sep 17 00:00:00 2001 From: Jakub Hrozek Date: Mon, 28 Nov 2016 08:44:04 +0100 Subject: [PATCH 38/39] STAP: Only print transaction statistics if the script caught some transactions MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If the script measured an 'id' run from the cache, there would be no transactions and dereferencing the aggrefate would throw an error. Reviewed-by: Fabiano Fidêncio (cherry picked from commit 150a0cc8fe1936002af136e5552ef6cdd210956f) (cherry picked from commit e6c74de2cbc9b0b713ed6dadbfef80c7c1b5cd51) --- contrib/systemtap/id_perf.stp | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/contrib/systemtap/id_perf.stp b/contrib/systemtap/id_perf.stp index 0ad619506..a7789750f 100644 --- a/contrib/systemtap/id_perf.stp +++ b/contrib/systemtap/id_perf.stp @@ -64,8 +64,10 @@ function print_report() } } - printf("The most expensive transaction breakdown, per transaction:\n") - print(@hist_linear(bts[max_trans_time_bt], 0, 500, 50)) + if (max_trans_time > 0) { + printf("The most expensive transaction breakdown, per transaction:\n") + print(@hist_linear(bts[max_trans_time_bt], 0, 500, 50)) + } } probe process("/usr/bin/id").begin -- 2.11.0