Merge pull request #6346 from MeirShpilraien/expose_zmalloc_capabilities

Expose used memory to modules via redismodule api

src/module.c

@@ -5995,6 +5995,26 @@ int RM_CommandFilterArgDelete(RedisModuleCommandFilterCtx *fctx, int pos)
     return REDISMODULE_OK;
 }
 
+/*
+ * For a given pointer, return The amount of memory
+ * allocated for this pointer.
+ */
+size_t RM_MallocSize(void* ptr){
+    return zmalloc_size(ptr);
+}
+
+/*
+ * Return the a number between 0 to 1 indicating
+ * the amount of memory currently used.
+ * 0 - no memory limit
+ * 1 and above, memory limit reached.
+ */
+float RM_GetUsedMemoryRatio(){
+    float level;
+    getMaxmemoryState(NULL, NULL, NULL, &level);
+    return level;
+}
+
 /* --------------------------------------------------------------------------
  * Scanning keyspace and hashes
  * -------------------------------------------------------------------------- */
@@ -7360,6 +7380,8 @@ void moduleRegisterCoreAPI(void) {
     REGISTER_API(BlockClientOnKeys);
     REGISTER_API(SignalKeyAsReady);
     REGISTER_API(GetBlockedClientReadyKey);
+    REGISTER_API(GetUsedMemoryRatio);
+    REGISTER_API(MallocSize);
     REGISTER_API(ScanCursorCreate);
     REGISTER_API(ScanCursorDestroy);
     REGISTER_API(ScanCursorRestart);

src/redismodule.h

@@ -649,6 +649,8 @@ int REDISMODULE_API_FUNC(RedisModule_CommandFilterArgDelete)(RedisModuleCommandF
 int REDISMODULE_API_FUNC(RedisModule_Fork)(RedisModuleForkDoneHandler cb, void *user_data);
 int REDISMODULE_API_FUNC(RedisModule_ExitFromChild)(int retcode);
 int REDISMODULE_API_FUNC(RedisModule_KillForkChild)(int child_pid);
+float REDISMODULE_API_FUNC(RedisModule_GetUsedMemoryRatio)();
+size_t REDISMODULE_API_FUNC(RedisModule_MallocSize)(void* ptr);
 #endif
 
 #define RedisModule_IsAOFClient(id) ((id) == UINT64_MAX)
@@ -871,6 +873,8 @@ static int RedisModule_Init(RedisModuleCtx *ctx, const char *name, int ver, int
     REDISMODULE_GET_API(Fork);
     REDISMODULE_GET_API(ExitFromChild);
     REDISMODULE_GET_API(KillForkChild);
+    REDISMODULE_GET_API(GetUsedMemoryRatio);
+    REDISMODULE_GET_API(MallocSize);
 #endif
 
     if (RedisModule_IsModuleNameBusy && RedisModule_IsModuleNameBusy(name)) return REDISMODULE_ERR;