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| author | Simon Rettberg | 2016-03-23 19:01:38 +0100 |
|---|---|---|
| committer | Simon Rettberg | 2016-03-23 19:01:38 +0100 |
| commit | 6024da67725c7a5bd8a6bc5b898b703851865ff3 (patch) | |
| tree | 88b2d5bcf7a9272999837ae11fa9a9c8a5cb6a2a /src/fuse | |
| parent | [FUSE] Add new load balancing mechanism (diff) | |
| download | dnbd3-6024da67725c7a5bd8a6bc5b898b703851865ff3.tar.gz dnbd3-6024da67725c7a5bd8a6bc5b898b703851865ff3.tar.xz dnbd3-6024da67725c7a5bd8a6bc5b898b703851865ff3.zip | |
[FUSE] Wait a little longer before switching via new approach
Diffstat (limited to 'src/fuse')
| -rw-r--r-- | src/fuse/connection.c | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/src/fuse/connection.c b/src/fuse/connection.c index eb65940..990dd36 100644 --- a/src/fuse/connection.c +++ b/src/fuse/connection.c @@ -18,7 +18,8 @@ static const size_t SHORTBUF = 100; #define MAX_ALTS (8) #define MAX_HOSTS_PER_ADDRESS (2) -static const int MAX_CONSECUTIVE_FAILURES = 16; +// If a server wasn't reachable this many times, we slowly start skipping it on measurements +static const int FAIL_BACKOFF_START_COUNT = 8; #define RTT_COUNT (4) /* Module variables */ @@ -346,7 +347,6 @@ fail:; pthread_mutex_lock( &connection.sendMutex ); // then just set the fd to -1, but only if it's the same fd as ours, // as someone could have established a new connection already - logadd( LOG_DEBUG1, "RT: Local sock: %d, global: %d", sockFd, connection.sockFd ); if ( connection.sockFd == sockFd ) { connection.sockFd = -1; signal_call( connection.panicSignal ); @@ -427,7 +427,7 @@ static void addAltServers() slot = eIdx; break; } - if ( altservers[eIdx].consecutiveFails > MAX_CONSECUTIVE_FAILURES + if ( altservers[eIdx].consecutiveFails > FAIL_BACKOFF_START_COUNT && slot != -1 && altservers[slot].consecutiveFails < altservers[eIdx].consecutiveFails ) { slot = eIdx; } @@ -466,8 +466,8 @@ static void probeAltServers() alt_server_t * const srv = &altservers[altIndex]; if ( srv->host.type == 0 ) continue; - if ( !panic && srv->consecutiveFails > MAX_CONSECUTIVE_FAILURES - && srv->consecutiveFails % ( srv->consecutiveFails / 8 ) != 0 ) { + if ( !panic && srv->consecutiveFails > FAIL_BACKOFF_START_COUNT + && rand() % srv->consecutiveFails >= FAIL_BACKOFF_START_COUNT ) { continue; } if ( srv->rttIndex >= RTT_COUNT ) { @@ -556,11 +556,11 @@ fail:; // we switch no matter how small the difference to the current server is for ( int i = 0; i < MAX_ALTS; ++i ) { if ( i == bestIndex ) { - if ( altservers[i].bestCount < 30 ) { + if ( altservers[i].bestCount < 50 ) { altservers[i].bestCount += 2; } // Switch with increasing probability the higher the bestCount is - if ( altservers[i].bestCount > 5 && altservers[i].rtt < currentRtt && altservers[i].bestCount > rand() % 25 ) { + if ( altservers[i].bestCount > 12 && altservers[i].rtt < currentRtt && altservers[i].bestCount > rand() % 50 ) { doSwitch = true; } } else if ( altservers[i].bestCount > 0 ) { @@ -568,7 +568,7 @@ fail:; } } // This takes care of the situation where two servers alternate being the best server all the time - if ( doSwitch && currentIndex != -1 && altservers[bestIndex].bestCount - altservers[currentIndex].bestCount < 6 ) { + if ( doSwitch && currentIndex != -1 && altservers[bestIndex].bestCount - altservers[currentIndex].bestCount < 8 ) { doSwitch = false; } // Regular logic: Apply threshold when considering switch |