[LU-16977] Ofd_access_log_reader use fraction option wrongly

Wed, 6 Sep 2023 13:14:23 +0000

When ofd_access_log_reader has batch-fraction=100 (default), the calculation of the batch fraction is wrong.

Details:

In the below fragment the array sa is accessed beyond the upper boundary when

aa->fraction=100

lustre\utils\ofd_access_batch.c

void *alr_sort_and_print_thread(void *arg)

...

sa = calloc(nr, sizeof(*sa));

...

i = nr * aa->fraction / 100;
cut = sa[i];

It is unlikely will cause a segfault, but the threshold of IO ops counter for the the printed ALR's might be chosen wrongly. As a result aaccess_log_reader may send not complete set of ALR's when the fraction is 100%

Whamcloud Community JIRA

[LU-16977] Ofd_access_log_reader use fraction option wrongly