Added boolean variable to guard fallocate() calls

Summary:
Added boolean variable to guard fallocate() calls.
Set to false to prevent space leaks when tests fail.

Test Plan:
Compliles
Set to false and ran log device tests

Reviewers: sdong, lovro, igor

Reviewed By: igor

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D48027

include/rocksdb/env.h

@@ -68,6 +68,9 @@ struct EnvOptions {
    // If true, then use mmap to write data
   bool use_mmap_writes = true;
 
+  // If false, fallocate() calls are bypassed
+  bool allow_fallocate = true;
+
   // If true, set the FD_CLOEXEC on open fd.
   bool set_fd_cloexec = true;
 

include/rocksdb/options.h

@@ -1006,6 +1006,9 @@ struct DBOptions {
   // Default: false
   bool allow_mmap_writes;
 
+  // If false, fallocate() calls are bypassed
+  bool allow_fallocate;
+
   // Disable child process inherit open files. Default: true
   bool is_fd_close_on_exec;
 
@@ -1137,9 +1140,7 @@ struct DBOptions {
 // Options to control the behavior of a database (passed to DB::Open)
 struct Options : public DBOptions, public ColumnFamilyOptions {
   // Create an Options object with default values for all fields.
-  Options() :
-    DBOptions(),
-    ColumnFamilyOptions() {}
+  Options() : DBOptions(), ColumnFamilyOptions() {}
 
   Options(const DBOptions& db_options,
           const ColumnFamilyOptions& column_family_options)

util/env.cc

@@ -12,7 +12,6 @@
 #include <thread>
 #include "port/port.h"
 #include "port/sys_time.h"
-#include "port/port.h"
 
 #include "rocksdb/options.h"
 #include "util/arena.h"
@@ -283,6 +282,7 @@ void AssignEnvOptions(EnvOptions* env_options, const DBOptions& options) {
   env_options->set_fd_cloexec = options.is_fd_close_on_exec;
   env_options->bytes_per_sync = options.bytes_per_sync;
   env_options->rate_limiter = options.rate_limiter.get();
+  env_options->allow_fallocate = options.allow_fallocate;
 }
 
 }

util/env_posix.cc

@@ -351,6 +351,7 @@ class PosixMmapFile : public WritableFile {
   char* dst_;             // Where to write next  (in range [base_,limit_])
   char* last_sync_;       // Where have we synced up to
   uint64_t file_offset_;  // Offset of base_ in file
+  bool allow_fallocate_;  // If false, fallocate calls are bypassed
 #ifdef ROCKSDB_FALLOCATE_PRESENT
   bool fallocate_with_keep_size_;
 #endif
@@ -393,7 +394,7 @@ class PosixMmapFile : public WritableFile {
 
     TEST_KILL_RANDOM(rocksdb_kill_odds);
     // we can't fallocate with FALLOC_FL_KEEP_SIZE here
-    {
+    if (allow_fallocate_) {
       IOSTATS_TIMER_GUARD(allocate_nanos);
       int alloc_status = fallocate(fd_, 0, file_offset_, map_size_);
       if (alloc_status != 0) {
@@ -451,7 +452,8 @@ class PosixMmapFile : public WritableFile {
         limit_(nullptr),
         dst_(nullptr),
         last_sync_(nullptr),
-        file_offset_(0) {
+        file_offset_(0),
+        allow_fallocate_(options.allow_fallocate) {
 #ifdef ROCKSDB_FALLOCATE_PRESENT
     fallocate_with_keep_size_ = options.fallocate_with_keep_size;
 #endif
@@ -575,8 +577,12 @@ class PosixMmapFile : public WritableFile {
 #ifdef ROCKSDB_FALLOCATE_PRESENT
   virtual Status Allocate(off_t offset, off_t len) override {
     TEST_KILL_RANDOM(rocksdb_kill_odds);
-    int alloc_status = fallocate(
-        fd_, fallocate_with_keep_size_ ? FALLOC_FL_KEEP_SIZE : 0, offset, len);
+    int alloc_status = 0;
+    if (allow_fallocate_) {
+      alloc_status =
+          fallocate(fd_, fallocate_with_keep_size_ ? FALLOC_FL_KEEP_SIZE : 0,
+                    offset, len);
+    }
     if (alloc_status == 0) {
       return Status::OK();
     } else {
@@ -592,13 +598,17 @@ class PosixWritableFile : public WritableFile {
   const std::string filename_;
   int fd_;
   uint64_t filesize_;
+  bool allow_fallocate_;
 #ifdef ROCKSDB_FALLOCATE_PRESENT
   bool fallocate_with_keep_size_;
 #endif
 
  public:
   PosixWritableFile(const std::string& fname, int fd, const EnvOptions& options)
-      : filename_(fname), fd_(fd), filesize_(0) {
+      : filename_(fname),
+        fd_(fd),
+        filesize_(0),
+        allow_fallocate_(options.allow_fallocate) {
 #ifdef ROCKSDB_FALLOCATE_PRESENT
     fallocate_with_keep_size_ = options.fallocate_with_keep_size;
 #endif
@@ -660,8 +670,10 @@ class PosixWritableFile : public WritableFile {
       // We ignore error since failure of this operation does not affect
       // correctness.
       IOSTATS_TIMER_GUARD(allocate_nanos);
-      fallocate(fd_, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE,
-                filesize_, block_size * last_allocated_block - filesize_);
+      if (allow_fallocate_) {
+        fallocate(fd_, FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE, filesize_,
+                  block_size * last_allocated_block - filesize_);
+      }
 #endif
     }
 
@@ -714,9 +726,12 @@ class PosixWritableFile : public WritableFile {
   virtual Status Allocate(off_t offset, off_t len) override {
     TEST_KILL_RANDOM(rocksdb_kill_odds);
     IOSTATS_TIMER_GUARD(allocate_nanos);
-    int alloc_status;
-    alloc_status = fallocate(
-        fd_, fallocate_with_keep_size_ ? FALLOC_FL_KEEP_SIZE : 0, offset, len);
+    int alloc_status = 0;
+    if (allow_fallocate_) {
+      alloc_status =
+          fallocate(fd_, fallocate_with_keep_size_ ? FALLOC_FL_KEEP_SIZE : 0,
+                    offset, len);
+    }
     if (alloc_status == 0) {
       return Status::OK();
     } else {
@@ -1146,7 +1161,7 @@ class PosixEnv : public Env {
     } else {
       int fd = fileno(f);
 #ifdef ROCKSDB_FALLOCATE_PRESENT
-      fallocate(fd, FALLOC_FL_KEEP_SIZE, 0, 4 * 1024 * 1024);
+      fallocate(fd, FALLOC_FL_KEEP_SIZE, 0, 4 * 1024);
 #endif
       SetFD_CLOEXEC(fd, nullptr);
       result->reset(new PosixLogger(f, &PosixEnv::gettid, this));
@@ -1609,10 +1624,11 @@ class PosixEnv : public Env {
 
 };
 
-PosixEnv::PosixEnv() : checkedDiskForMmap_(false),
-                       forceMmapOff(false),
-                       page_size_(getpagesize()),
-                       thread_pools_(Priority::TOTAL) {
+PosixEnv::PosixEnv()
+    : checkedDiskForMmap_(false),
+      forceMmapOff(false),
+      page_size_(getpagesize()),
+      thread_pools_(Priority::TOTAL) {
   PthreadCall("mutex_init", pthread_mutex_init(&mu_, nullptr));
   for (int pool_id = 0; pool_id < Env::Priority::TOTAL; ++pool_id) {
     thread_pools_[pool_id].SetThreadPriority(

util/options.cc

@@ -239,6 +239,7 @@ DBOptions::DBOptions()
       allow_os_buffer(true),
       allow_mmap_reads(false),
       allow_mmap_writes(false),
+      allow_fallocate(true),
       is_fd_close_on_exec(true),
       skip_log_error_on_recovery(false),
       stats_dump_period_sec(600),
@@ -292,6 +293,7 @@ DBOptions::DBOptions(const Options& options)
       allow_os_buffer(options.allow_os_buffer),
       allow_mmap_reads(options.allow_mmap_reads),
       allow_mmap_writes(options.allow_mmap_writes),
+      allow_fallocate(options.allow_fallocate),
       is_fd_close_on_exec(options.is_fd_close_on_exec),
       skip_log_error_on_recovery(options.skip_log_error_on_recovery),
       stats_dump_period_sec(options.stats_dump_period_sec),
@@ -338,6 +340,7 @@ void DBOptions::Dump(Logger* log) const {
          keep_log_file_num);
     Header(log, "       Options.allow_os_buffer: %d", allow_os_buffer);
     Header(log, "      Options.allow_mmap_reads: %d", allow_mmap_reads);
+    Header(log, "      Options.allow_fallocate: %d", allow_fallocate);
     Header(log, "     Options.allow_mmap_writes: %d", allow_mmap_writes);
     Header(log, "         Options.create_missing_column_families: %d",
         create_missing_column_families);

util/options_helper.h

@@ -122,6 +122,9 @@ static std::unordered_map<std::string, OptionTypeInfo> db_options_type_info = {
     {"allow_mmap_reads",
      {offsetof(struct DBOptions, allow_mmap_reads), OptionType::kBoolean,
       OptionVerificationType::kNormal}},
+    {"allow_fallocate",
+     {offsetof(struct DBOptions, allow_fallocate), OptionType::kBoolean,
+      OptionVerificationType::kNormal}},
     {"allow_mmap_writes",
      {offsetof(struct DBOptions, allow_mmap_writes), OptionType::kBoolean,
       OptionVerificationType::kNormal}},