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Merged
merged 2 commits into from
Jun 20, 2022
Merged

Extend cachbench with touch value #85

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98a2fde
Extend cachbench with touch value
igchor May 4, 2022
21c2e31
Enable touchValue by default
igchor Jun 15, 2022
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36 changes: 12 additions & 24 deletions cachelib/cachebench/cache/Cache-inl.h
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Original file line number Diff line number Diff line change
Expand Up @@ -50,8 +50,10 @@ uint64_t Cache<Allocator>::fetchNandWrites() const {
template <typename Allocator>
Cache<Allocator>::Cache(const CacheConfig& config,
ChainedItemMovingSync movingSync,
std::string cacheDir)
std::string cacheDir,
bool touchValue)
: config_(config),
touchValue_(touchValue),
nandBytesBegin_{fetchNandWrites()},
itemRecords_(config_.enableItemDestructorCheck) {
constexpr size_t MB = 1024ULL * 1024ULL;
Expand Down Expand Up @@ -325,22 +327,13 @@ template <typename Allocator>
void Cache<Allocator>::enableConsistencyCheck(
const std::vector<std::string>& keys) {
XDCHECK(valueTracker_ == nullptr);
XDCHECK(!valueValidatingEnabled());
valueTracker_ =
std::make_unique<ValueTracker>(ValueTracker::wrapStrings(keys));
for (const std::string& key : keys) {
invalidKeys_[key] = false;
}
}

template <typename Allocator>
void Cache<Allocator>::enableValueValidating(
const std::string &expectedValue) {
XDCHECK(!valueValidatingEnabled());
XDCHECK(!consistencyCheckEnabled());
this->expectedValue_ = expectedValue;
}

template <typename Allocator>
typename Cache<Allocator>::RemoveRes Cache<Allocator>::remove(Key key) {
if (!consistencyCheckEnabled()) {
Expand Down Expand Up @@ -434,17 +427,15 @@ typename Cache<Allocator>::ItemHandle Cache<Allocator>::insertOrReplace(
}

template <typename Allocator>
void Cache<Allocator>::validateValue(const ItemHandle &it) const {
XDCHECK(valueValidatingEnabled());

const auto &expected = expectedValue_.value();
void Cache<Allocator>::touchValue(const ItemHandle& it) const {
XDCHECK(touchValueEnabled());

auto ptr = reinterpret_cast<const uint8_t*>(getMemory(it));
auto cmp = std::memcmp(ptr, expected.data(), std::min<size_t>(expected.size(),
getSize(it)));
if (cmp != 0) {
throw std::runtime_error("Value does not match!");
}

/* The accumulate call is intended to access all bytes of the value
* and nothing more. */
auto sum = std::accumulate(ptr, ptr + getSize(it), 0ULL);
folly::doNotOptimizeAway(sum);
}

template <typename Allocator>
Expand All @@ -459,9 +450,8 @@ typename Cache<Allocator>::ItemHandle Cache<Allocator>::find(Key key,
auto it = cache_->find(key, mode);
it.wait();

if (valueValidatingEnabled()) {
XDCHECK(!consistencyCheckEnabled());
validateValue(it);
if (touchValueEnabled()) {
touchValue(it);
}

return it;
Expand All @@ -472,8 +462,6 @@ typename Cache<Allocator>::ItemHandle Cache<Allocator>::find(Key key,
return it;
}

XDCHECK(!valueValidatingEnabled());

auto opId = valueTracker_->beginGet(key);
auto it = findFn();
if (checkGet(opId, it)) {
Expand Down
19 changes: 9 additions & 10 deletions cachelib/cachebench/cache/Cache.h
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Original file line number Diff line number Diff line change
Expand Up @@ -64,9 +64,11 @@ class Cache {
// cache.
// @param cacheDir optional directory for the cache to enable
// persistence across restarts.
// @param touchValue read entire value on find
explicit Cache(const CacheConfig& config,
ChainedItemMovingSync movingSync = {},
std::string cacheDir = "");
std::string cacheDir = "",
bool touchValue = true);

~Cache();

Expand Down Expand Up @@ -168,8 +170,8 @@ class Cache {
return getSize(item.get());
}

// checks if values stored in it matches expectedValue_.
void validateValue(const ItemHandle &it) const;
// read entire value on find.
void touchValue(const ItemHandle& it) const;

// returns the size of the item, taking into account ItemRecords could be
// enabled.
Expand Down Expand Up @@ -228,14 +230,11 @@ class Cache {
// @param keys list of keys that the stressor uses for the workload.
void enableConsistencyCheck(const std::vector<std::string>& keys);

// enables validating all values on find. Each value is compared to
// expected Value.
void enableValueValidating(const std::string &expectedValue);

// returns true if the consistency checking is enabled.
bool consistencyCheckEnabled() const { return valueTracker_ != nullptr; }

bool valueValidatingEnabled() const { return expectedValue_.has_value(); }
// returns true if touching value is enabled.
bool touchValueEnabled() const { return touchValue_; }

// return true if the key was previously detected to be inconsistent. This
// is useful only when consistency checking is enabled by calling
Expand Down Expand Up @@ -359,8 +358,8 @@ class Cache {
// tracker for consistency monitoring.
std::unique_ptr<ValueTracker> valueTracker_;

// exceptected value of all items in Cache.
std::optional<std::string> expectedValue_;
// read entire value on find.
bool touchValue_{true};

// reading of the nand bytes written for the benchmark if enabled.
const uint64_t nandBytesBegin_{0};
Expand Down
6 changes: 2 additions & 4 deletions cachelib/cachebench/runner/CacheStressor.h
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Original file line number Diff line number Diff line change
Expand Up @@ -93,7 +93,8 @@ class CacheStressor : public Stressor {
cacheConfig.ticker = ticker_;
}

cache_ = std::make_unique<CacheT>(cacheConfig, movingSync);
cache_ = std::make_unique<CacheT>(cacheConfig, movingSync, "",
config_.touchValue);
if (config_.opPoolDistribution.size() > cache_->numPools()) {
throw std::invalid_argument(folly::sformat(
"more pools specified in the test than in the cache. "
Expand All @@ -110,9 +111,6 @@ class CacheStressor : public Stressor {
if (config_.checkConsistency) {
cache_->enableConsistencyCheck(wg_->getAllKeys());
}
if (config_.validateValue) {
cache_->enableValueValidating(hardcodedString_);
}
if (config_.opRatePerSec > 0) {
rateLimiter_ = std::make_unique<folly::BasicTokenBucket<>>(
config_.opRatePerSec, config_.opRatePerSec);
Expand Down
2 changes: 1 addition & 1 deletion cachelib/cachebench/util/Config.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -34,7 +34,7 @@ StressorConfig::StressorConfig(const folly::dynamic& configJson) {
JSONSetVal(configJson, samplingIntervalMs);

JSONSetVal(configJson, checkConsistency);
JSONSetVal(configJson, validateValue);
JSONSetVal(configJson, touchValue);

JSONSetVal(configJson, numOps);
JSONSetVal(configJson, numThreads);
Expand Down
4 changes: 4 additions & 0 deletions cachelib/cachebench/util/Config.h
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Original file line number Diff line number Diff line change
Expand Up @@ -195,6 +195,10 @@ struct StressorConfig : public JSONConfig {
// Mutually exclusive with checkConsistency
bool validateValue{false};

// If enabled, each value will be read on find. This is useful for measuring
// performance of value access.
bool touchValue{true};

uint64_t numOps{0}; // operation per thread
uint64_t numThreads{0}; // number of threads that will run
uint64_t numKeys{0}; // number of keys that will be used
Expand Down