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https://github.com/google/leveldb.git
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0cfb990d58
- switched from mmap based writing to simpler stdio based writing. Has a minor impact (0.5 microseconds) on microbenchmarks for asynchronous writes. Synchronous writes speed up from 30ms to 10ms on linux/ext4. Should be much more reliable on diverse platforms. - compaction errors now immediately put the database into a read-only mode (until it is re-opened). As a downside, a disk going out of space and then space being created will require a re-open to recover from, whereas previously that would happen automatically. On the plus side, many corruption possibilities go away. - force the DB to enter an error-state so that all future writes fail when a synchronous log write succeeds but the sync fails. - repair now regenerates sstables that exhibit problems - fix issue 218 - Use native memory barriers on OSX - fix issue 212 - QNX build is broken - fix build on iOS with xcode 5 - make tests compile and pass on windows
52 lines
1.4 KiB
C++
52 lines
1.4 KiB
C++
// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file. See the AUTHORS file for names of contributors.
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#include "util/testutil.h"
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#include "util/random.h"
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namespace leveldb {
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namespace test {
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Slice RandomString(Random* rnd, int len, std::string* dst) {
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dst->resize(len);
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for (int i = 0; i < len; i++) {
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(*dst)[i] = static_cast<char>(' ' + rnd->Uniform(95)); // ' ' .. '~'
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}
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return Slice(*dst);
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}
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std::string RandomKey(Random* rnd, int len) {
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// Make sure to generate a wide variety of characters so we
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// test the boundary conditions for short-key optimizations.
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static const char kTestChars[] = {
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'\0', '\1', 'a', 'b', 'c', 'd', 'e', '\xfd', '\xfe', '\xff'
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};
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std::string result;
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for (int i = 0; i < len; i++) {
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result += kTestChars[rnd->Uniform(sizeof(kTestChars))];
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}
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return result;
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}
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extern Slice CompressibleString(Random* rnd, double compressed_fraction,
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size_t len, std::string* dst) {
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int raw = static_cast<int>(len * compressed_fraction);
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if (raw < 1) raw = 1;
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std::string raw_data;
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RandomString(rnd, raw, &raw_data);
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// Duplicate the random data until we have filled "len" bytes
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dst->clear();
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while (dst->size() < len) {
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dst->append(raw_data);
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}
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dst->resize(len);
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return Slice(*dst);
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}
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} // namespace test
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} // namespace leveldb
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