Fix a bug in stall time counter. Improve its output format.

Summary: Fix a bug in stall time counter.  Improve its output format.

Test Plan:
export ROCKSDB_TESTS=Timeout
./db_test

./db_bench --benchmarks=fillrandom --stats_interval=10000 --statistics=true --stats_per_interval=1 --num=1000000 --threads=4 --level0_stop_writes_trigger=3 --level0_slowdown_writes_trigger=2

sample output:
    Uptime(secs): 35.8 total, 0.0 interval
    Cumulative writes: 359590 writes, 359589 keys, 183047 batches, 2.0 writes per batch, 0.04 GB user ingest, stall seconds: 1786.008 ms
    Cumulative WAL: 359591 writes, 183046 syncs, 1.96 writes per sync, 0.04 GB written
    Interval writes: 253 writes, 253 keys, 128 batches, 2.0 writes per batch, 0.0 MB user ingest, stall time: 0 us
    Interval WAL: 253 writes, 128 syncs, 1.96 writes per sync, 0.00 MB written

Reviewers: MarkCallaghan, igor, sdong

Reviewed By: sdong

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D34275
This commit is contained in:
Yueh-Hsuan Chiang 2015-03-03 12:48:12 -08:00
parent b8d23cdcb8
commit 694988b627
4 changed files with 35 additions and 5 deletions

View File

@ -3233,6 +3233,7 @@ Status DBImpl::Write(const WriteOptions& write_options, WriteBatch* my_batch) {
Status DBImpl::DelayWrite(uint64_t expiration_time) {
uint64_t time_delayed = 0;
bool delayed = false;
bool timed_out = false;
{
StopWatch sw(env_, stats_, WRITE_STALL, &time_delayed);
bool has_timeout = (expiration_time > 0);
@ -3250,7 +3251,8 @@ Status DBImpl::DelayWrite(uint64_t expiration_time) {
if (has_timeout) {
bg_cv_.TimedWait(expiration_time);
if (env_->NowMicros() > expiration_time) {
return Status::TimedOut();
timed_out = true;
break;
}
} else {
bg_cv_.Wait();
@ -3263,6 +3265,10 @@ Status DBImpl::DelayWrite(uint64_t expiration_time) {
RecordTick(stats_, STALL_MICROS, time_delayed);
}
if (timed_out) {
return Status::TimedOut();
}
return bg_error_;
}

View File

@ -312,6 +312,9 @@ void InternalStats::DumpDBStats(std::string* value) {
uint64_t wal_synced = db_stats_[InternalStats::WAL_FILE_SYNCED];
uint64_t write_with_wal = db_stats_[InternalStats::WRITE_WITH_WAL];
uint64_t write_stall_micros = db_stats_[InternalStats::WRITE_STALL_MICROS];
const int kHumanMicrosLen = 32;
char human_micros[kHumanMicrosLen];
// Data
// writes: total number of write requests.
// keys: total number of key updates issued by all the write requests
@ -321,13 +324,14 @@ void InternalStats::DumpDBStats(std::string* value) {
// writes/batches is the average group commit size.
//
// The format is the same for interval stats.
AppendHumanMicros(write_stall_micros, human_micros, kHumanMicrosLen);
snprintf(buf, sizeof(buf),
"Cumulative writes: %" PRIu64 " writes, %" PRIu64 " keys, %" PRIu64
" batches, %.1f writes per batch, %.2f GB user ingest, "
"stall micros: %" PRIu64 "\n",
"stall time: %s\n",
write_other + write_self, num_keys_written, write_self,
(write_other + write_self) / static_cast<double>(write_self + 1),
user_bytes_written / kGB, write_stall_micros);
user_bytes_written / kGB, human_micros);
value->append(buf);
// WAL
snprintf(buf, sizeof(buf),
@ -343,16 +347,19 @@ void InternalStats::DumpDBStats(std::string* value) {
uint64_t interval_write_self = write_self - db_stats_snapshot_.write_self;
uint64_t interval_num_keys_written =
num_keys_written - db_stats_snapshot_.num_keys_written;
AppendHumanMicros(
write_stall_micros - db_stats_snapshot_.write_stall_micros,
human_micros, kHumanMicrosLen);
snprintf(buf, sizeof(buf),
"Interval writes: %" PRIu64 " writes, %" PRIu64 " keys, %" PRIu64
" batches, %.1f writes per batch, %.1f MB user ingest, "
"stall micros: %" PRIu64 "\n",
"stall time: %s\n",
interval_write_other + interval_write_self,
interval_num_keys_written, interval_write_self,
static_cast<double>(interval_write_other + interval_write_self) /
(interval_write_self + 1),
(user_bytes_written - db_stats_snapshot_.ingest_bytes) / kMB,
write_stall_micros - db_stats_snapshot_.write_stall_micros);
human_micros);
value->append(buf);
uint64_t interval_write_with_wal =

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@ -23,6 +23,20 @@
namespace rocksdb {
// for micros < 10ms, print "XX us".
// for micros < 10sec, print "XX ms".
// for micros >= 10 sec, print "XX sec".
int AppendHumanMicros(uint64_t micros, char* output, int len) {
if (micros < 10000) {
return snprintf(output, len, "%" PRIu64 " us", micros);
} else if (micros < 10000000) {
return snprintf(output, len, "%.3lf ms",
static_cast<double>(micros) / 1000);
} else {
return snprintf(output, len, "%.3lf sec",
static_cast<double>(micros) / 1000000);
}
}
// for sizes >=10TB, print "XXTB"
// for sizes >=10GB, print "XXGB"

View File

@ -20,6 +20,9 @@ namespace rocksdb {
class Slice;
// Append a human-readable time in micros.
int AppendHumanMicros(uint64_t micros, char* output, int len);
// Append a human-readable size in bytes
int AppendHumanBytes(uint64_t bytes, char* output, int len);