[IMPALA-6895] Reduce flush, close and open calls in SimpleLogger::flush()

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Won't Do
• Affects Version/s: Impala 3.0
• Component/s: Backend
• Labels: ramp-up
• Epic Color: ghx-label-8
• Assignee: Unassigned
• Reporter: Zoram Thanga
• Created: 19/Apr/18 23:56
• Updated: 09/Jan/21 01:57
• Resolved: 09/Jan/21 01:57

Description

Currently, SimpleLogger provides a Flush() interface which is used by its client(s) to periodically (hard-coded to 5 seconds) flush the log file. We could eliminate these flush threads by keeping track of last flush time, and have the caller of SimpleLogger::AppendEntry() flush on demand (now - last_flush_time >= 5 seconds or whatever).

This has the added benefit of reducing contention on the SimpleLogger::log_file_lock_ mutex to just between the threads adding entries to the log file.