Enabled memory tier config API for cachebench.

Author: victoria-mcgrath

cachelib/cachebench/cache/Cache-inl.h

@@ -94,6 +94,20 @@ Cache<Allocator>::Cache(const CacheConfig& config,
 
   allocatorConfig_.setCacheSize(config_.cacheSizeMB * (MB));
 
+  if (!cacheDir.empty()) {
+    allocatorConfig_.cacheDir = cacheDir;
+  } else if (!config_.persistedCacheDir.empty()) {
+      allocatorConfig_.enableCachePersistence(config_.persistedCacheDir);
+  }
+
+  if (config_.usePosixShm) {
+    allocatorConfig_.usePosixForShm();
+  }
+
+  if (config_.memoryTierConfigs.size()) {
+    allocatorConfig_.configureMemoryTiers(config_.memoryTierConfigs);
+  }
+
   auto cleanupGuard = folly::makeGuard([&] {
     if (!nvmCacheFilePath_.empty()) {
       util::removePath(nvmCacheFilePath_);
@@ -244,8 +258,7 @@ Cache<Allocator>::Cache(const CacheConfig& config,
 
   allocatorConfig_.cacheName = "cachebench";
 
-  if (!cacheDir.empty()) {
-    allocatorConfig_.cacheDir = cacheDir;
+  if (!allocatorConfig_.cacheDir.empty()) {
     cache_ =
         std::make_unique<Allocator>(Allocator::SharedMemNew, allocatorConfig_);
   } else {

cachelib/cachebench/test_configs/simple_tiers_test.json

@@ -0,0 +1,36 @@
+// @nolint instantiates a small cache and runs a quick run of basic operations.
+{
+  "cache_config" : {
+    "cacheSizeMB" : 512,
+    "usePosixShm" : true,
+    "persistedCacheDir" : "/tmp/mem-tiers",
+    "memoryTiers" : [
+      {
+        "ratio": 1,
+        "file": "/tmp/mem-tiers/memory-mapped-tier"
+      }
+    ],
+    "poolRebalanceIntervalSec" : 1,
+    "moveOnSlabRelease" : false,
+
+    "numPools" : 2,
+    "poolSizes" : [0.3, 0.7]
+  },
+  "test_config" : {
+      "numOps" : 100000,
+      "numThreads" : 32,
+      "numKeys" : 1000000,
+
+      "keySizeRange" : [1, 8, 64],
+      "keySizeRangeProbability" : [0.3, 0.7],
+
+      "valSizeRange" : [1, 32, 10240, 409200],
+      "valSizeRangeProbability" : [0.1, 0.2, 0.7],
+
+      "getRatio" : 0.15,
+      "setRatio" : 0.8,
+      "delRatio" : 0.05,
+      "keyPoolDistribution": [0.4, 0.6],
+      "opPoolDistribution" : [0.5, 0.5]
+  }
+}

cachelib/cachebench/util/CacheConfig.cpp

@@ -93,10 +93,18 @@ CacheConfig::CacheConfig(const folly::dynamic& configJson) {
   JSONSetVal(configJson, enableItemDestructorCheck);
   JSONSetVal(configJson, enableItemDestructor);
 
+  JSONSetVal(configJson, persistedCacheDir);
+  JSONSetVal(configJson, usePosixShm);
+  if (configJson.count("memoryTiers")) {
+    for (auto& it : configJson["memoryTiers"]) {
+      memoryTierConfigs.push_back(MemoryTierConfig(it).getMemoryTierCacheConfig());
+    }
+  }
+
   // if you added new fields to the configuration, update the JSONSetVal
   // to make them available for the json configs and increment the size
   // below
-  checkCorrectSize<CacheConfig, 688>();
+  checkCorrectSize<CacheConfig, 752>();
 
   if (numPools != poolSizes.size()) {
     throw std::invalid_argument(folly::sformat(
@@ -125,6 +133,16 @@ std::shared_ptr<RebalanceStrategy> CacheConfig::getRebalanceStrategy() const {
         RandomStrategy::Config{static_cast<unsigned int>(rebalanceMinSlabs)});
   }
 }
+
+
+MemoryTierConfig::MemoryTierConfig(const folly::dynamic& configJson) {
+  JSONSetVal(configJson, file);
+  JSONSetVal(configJson, ratio);
+  JSONSetVal(configJson, size);
+
+  checkCorrectSize<MemoryTierConfig, 48>();
+}
+
 } // namespace cachebench
 } // namespace cachelib
 } // namespace facebook

cachelib/cachebench/util/CacheConfig.h

@@ -41,6 +41,23 @@ class CacheMonitorFactory {
   virtual std::unique_ptr<CacheMonitor> create(Lru2QAllocator& cache) = 0;
 };
 
+struct MemoryTierConfig : public JSONConfig {
+  MemoryTierConfig() {}
+
+  explicit MemoryTierConfig(const folly::dynamic& configJson);
+  MemoryTierCacheConfig getMemoryTierCacheConfig() {
+    if (file.empty()) {
+      throw std::invalid_argument("Please specify valid path to memory mapped file.");
+    }
+    MemoryTierCacheConfig config = MemoryTierCacheConfig::fromFile(file).setSize(size).setRatio(ratio);
+    return config;
+  }
+
+  std::string file{""};
+  size_t ratio{0};
+  size_t size{0};
+};
+
 struct CacheConfig : public JSONConfig {
   // by defaullt, lru allocator. can be set to LRU-2Q.
   std::string allocator{"LRU"};
@@ -194,6 +211,13 @@ struct CacheConfig : public JSONConfig {
   // Not used when its value is 0.  In seconds.
   uint32_t memoryOnlyTTL{0};
 
+  // Directory for the cache to enable persistence across restarts.
+  std::string persistedCacheDir{""};
+
+  bool usePosixShm{false};
+
+  std::vector<MemoryTierCacheConfig> memoryTierConfigs{};
+
   // If enabled, we will use nvm admission policy tuned for ML use cases
   std::string mlNvmAdmissionPolicy{""};