Setting min_free_kbytes too high will cause system hangs, especially in i386 arch, using less than 5% of total memory can avoid it, so choose %5 of free memory or 2% of total memory. Thanks Shuang pointed out it.
also, in order to enlarge the coverage, the patch adds a new case item: 2 * default tunable Signed-off-by: Zhouping Liu <[email protected]> Signed-off-by: Shuang Qiu <[email protected]> --- testcases/kernel/mem/tunable/min_free_kbytes.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/testcases/kernel/mem/tunable/min_free_kbytes.c b/testcases/kernel/mem/tunable/min_free_kbytes.c index 00ead04..f8288ec 100644 --- a/testcases/kernel/mem/tunable/min_free_kbytes.c +++ b/testcases/kernel/mem/tunable/min_free_kbytes.c @@ -10,7 +10,8 @@ * the current free memory with the tunable value repeatedly. * * a) default min_free_kbytes with all overcommit memory policy - * b) half of mem_free with all overcommit memory policy + * b) 2x default value with all overcommit memory policy + * c) 5% of MemFree or %2 MemTotal with all overcommit memory policy * ******************************************************************** * Copyright (C) 2012 Red Hat, Inc. @@ -115,20 +116,27 @@ int main(int argc, char *argv[]) static void test_tune(unsigned long overcommit_policy) { int status; - int pid[2]; + int pid[3]; int ret, i; - unsigned long tune, memfree; + unsigned long tune, memfree, memtotal; set_sys_tune("overcommit_memory", overcommit_policy, 1); - for (i = 0; i < 2; i++) { + for (i = 0; i < 3; i++) { /* case1 */ if (i == 0) set_sys_tune("min_free_kbytes", default_tune, 1); /* case2 */ - else { + else if (i == 1) { + set_sys_tune("min_free_kbytes", 2 * default_tune, 1); + /* case3 */ + } else { memfree = read_meminfo("MemFree:"); - tune = memfree / 2; + memtotal = read_meminfo("MemTotal:"); + tune = memfree / 20; + if (tune > (memtotal / 50)) + tune = memtotal / 50; + set_sys_tune("min_free_kbytes", tune, 1); } -- 1.7.11.2 ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Ltp-list mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/ltp-list
