Continuing the investigation that started in cri-o/cri-o#6973
Apparently, sometimes systemd removes the cgroup before conmon can read its memory.events. I don't have any ideas about how to work around that race (in conmon; that is).
Another small issue I found is sometimes OOM can be misdetected because the code use the same static counter variable for both oom and oom_kill, which appears to be wrong.
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gboolean check_cgroup2_oom() |
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{ |
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static long int last_counter = 0; |
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if (!is_cgroup_v2) |
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return G_SOURCE_REMOVE; |
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_cleanup_free_ char *memory_events_file_path = g_build_filename(cgroup2_path, "memory.events", NULL); |
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_cleanup_fclose_ FILE *fp = fopen(memory_events_file_path, "re"); |
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if (fp == NULL) { |
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nwarnf("Failed to open cgroups file: %s", memory_events_file_path); |
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return G_SOURCE_CONTINUE; |
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} |
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_cleanup_free_ char *line = NULL; |
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size_t len = 0; |
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ssize_t read; |
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while ((read = getline(&line, &len, fp)) != -1) { |
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long int counter; |
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const int oom_len = 4, oom_kill_len = 9; |
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if (read >= oom_kill_len + 2 && memcmp(line, "oom_kill ", oom_kill_len) == 0) |
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len = oom_kill_len; |
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else if (read >= oom_len + 2 && memcmp(line, "oom ", oom_len) == 0) |
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len = oom_len; |
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else |
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continue; |
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counter = strtol(&line[len], NULL, 10); |
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if (counter == LONG_MAX) { |
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nwarnf("Failed to parse: %s", &line[len]); |
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continue; |
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} |
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if (counter == 0) |
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continue; |
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if (counter != last_counter) { |
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if (write_oom_files() == 0) |
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last_counter = counter; |