andreacavalli/rocksdb
0
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity
5,479 Commits 152 Branches 236 Tags 271 MiB
e489270980
Commit Graph

7 Commits

Author SHA1 Message Date
Peter (Stig) Edwards
f8d8cf53fe Fix log_write_bench -bytes_per_sync option. (#1375) 
Hello and thanks for RocksDB,
 
When log_write_bench is run with the -bytes_per_sync option, the option does not influence any *sync* behaviour.
 
> strace -e trace=write,sync_file_range ./log_write_bench -record_interval 0 -record_size 1048576 -num_records 11 -bytes_per_sync 2097152 2>&1 | egrep '^(sync|write.*XXXX)'
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
 
I suspect that this is because the bytes_per_sync option now needs to be using a `WritableFileWriter` and not a `WritableFile`.
 
With the diff below applied, it changes to:
 
> strace -e trace=write,sync_file_range ./log_write_bench -record_interval 0 -record_size 1048576 -num_records 11 -bytes_per_sync 2097152 2>&1 | egrep '^(sync|write.*XXXX)'
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
sync_file_range(0x3, 0, 0x200000, 0x2)  = 0
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
sync_file_range(0x3, 0x200000, 0x200000, 0x2) = 0
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
sync_file_range(0x3, 0x400000, 0x200000, 0x2) = 0
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
sync_file_range(0x3, 0x600000, 0x200000, 0x2) = 0
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 1048576) = 1048576
sync_file_range(0x3, 0x800000, 0x200000, 0x2) = 0
 
( Note that the first 1MB is not synced as mentioned in util/file_reader_writer.cc::WritableFileWriter::Flush() )
 
This diff also includes the fix from https://github.com/facebook/rocksdb/pull/1373
 
> diff -du util/log_write_bench.cc.orig util/log_write_bench.cc
--- util/log_write_bench.cc.orig        2016-10-04 12:06:29.115122580 -0400
+++ util/log_write_bench.cc     2016-10-05 07:24:09.677037576 -0400
@@ -14,6 +14,7 @@
 #include <gflags/gflags.h>

 #include "rocksdb/env.h"
+#include "util/file_reader_writer.h"
 #include "util/histogram.h"
 #include "util/testharness.h"
 #include "util/testutil.h"
@@ -38,19 +39,21 @@
   env_options.bytes_per_sync = FLAGS_bytes_per_sync;
   unique_ptr<WritableFile> file;
   env->NewWritableFile(file_name, &file, env_options);
+  unique_ptr<WritableFileWriter> writer;
+  writer.reset(new WritableFileWriter(std::move(file), env_options));

   std::string record;
-  record.assign('X', FLAGS_record_size);
+  record.assign(FLAGS_record_size, 'X');

   HistogramImpl hist;

   uint64_t start_time = env->NowMicros();
   for (int i = 0; i < FLAGS_num_records; i++) {
     uint64_t start_nanos = env->NowNanos();
-    file->Append(record);
-    file->Flush();
+    writer->Append(record);
+    writer->Flush();
     if (FLAGS_enable_sync) {
-      file->Sync();
+      writer->Sync(false);
     }
     hist.Add(env->NowNanos() - start_nanos);
 2016-10-11 16:45:51 -07:00
Peter (Stig) Edwards
043cb62d63 Fix record_size in log_write_bench, swap args to std::string::assign. (#1373) 
Hello and thank you for RocksDB,
 
I noticed when using log_write_bench that writes were always 88 bytes:
 
> strace -e trace=write ./log_write_bench -num_records 2 2>&1 | head -n 2
write(3, "\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371"..., 88) = 88
write(3, "\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371\371"..., 88) = 88

> strace -e trace=write ./log_write_bench -record_size 4096 -num_records 2 2>&1 | head -n 2
write(3, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 88) = 88
write(3, "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 88) = 88
 
I think this should be:

<<    record.assign('X', FLAGS_record_size);
>>    record.assign(FLAGS_record_size, 'X');

So fill and not buffer. Otherwise I always see writes of size 88 (the decimal value for chr "X").

string& assign (const char* s, size_t n);
buffer - Copies the first n characters from the array of characters pointed by s.

string& assign (size_t n, char c);
fill   - Replaces the current value by n consecutive copies of character c.

perl -le 'print ord "X"'
88
 
With the change:
 
> strace -e trace=write ./log_write_bench -record_size 4096 -num_records 2 2>&1 | head -n 2
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 4096) = 4096
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 4096) = 4096
 
> strace -e trace=write ./log_write_bench -num_records 2 2>&1 | head -n 2
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 249) = 249
write(3, "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"..., 249) = 249

Thanks.

01c27be5fb
https://reviews.facebook.net/D16239
 2016-10-06 10:45:31 -07:00
Baraa Hamodi
21e95811d1 Updated all copyright headers to the new format. 2016-02-09 15:12:00 -08:00
Igor Canadi
fec4269966 Fix more gflag namespace issues 2014-05-09 08:41:02 -07:00
Igor Canadi
8dc34364d2 Rename "benchmark" back to "bench". 
Also, make `benchharness.cc` not compiled into rocksdb library.
 2014-04-21 13:12:15 -07:00
Pratyush Seth
ff1b5df4c6 Added benchmark functionality on the lines of folly/Benchmark.h 
Summary: Added benchmark functionality on the lines of folly/Benchmark.h

Test Plan: Added unit tests

Reviewers: igor, haobo, sdong, ljin, yhchiang, dhruba

Reviewed By: igor

CC: leveldb

Differential Revision: https://reviews.facebook.net/D17973
 2014-04-21 12:29:55 -07:00
sdong
01c27be5fb A simple benchmark to measure WAL append latency 
Summary: A simple benchmark that simulates WAL append. It can be used to test different platform/file system's performance on WAL.

Test Plan: run it.

Reviewers: haobo, kailiu

Reviewed By: haobo

CC: igor, dhruba, i.am.jin.lei, yhchiang, leveldb, nkg-

Differential Revision: https://reviews.facebook.net/D16239
 2014-02-24 14:39:32 -08:00