@ -13,14 +13,9 @@
# include "monitoring/statistics.h"
# include "port/port.h"
# include "rocksdb/convenience.h"
# include "rocksdb/system_clock.h"
# include "rocksdb/utilities/customizable_util.h"
# include "rocksdb/utilities/object_registry.h"
# include "rocksdb/utilities/options_type.h"
# include "test_util/sync_point.h"
# include "util/aligned_buffer.h"
# include "util/string_util.h"
namespace ROCKSDB_NAMESPACE {
size_t RateLimiter : : RequestToken ( size_t bytes , size_t alignment ,
@ -50,68 +45,33 @@ struct GenericRateLimiter::Req {
bool granted ;
} ;
static std : : unordered_map < std : : string , OptionTypeInfo >
generic_rate_limiter_type_info = {
# ifndef ROCKSDB_LITE
{ " rate_bytes_per_sec " ,
{ offsetof ( struct GenericRateLimiter : : GenericRateLimiterOptions ,
max_bytes_per_sec ) ,
OptionType : : kInt64T } } ,
{ " refill_period_us " ,
{ offsetof ( struct GenericRateLimiter : : GenericRateLimiterOptions ,
refill_period_us ) ,
OptionType : : kInt64T } } ,
{ " fairness " ,
{ offsetof ( struct GenericRateLimiter : : GenericRateLimiterOptions ,
fairness ) ,
OptionType : : kInt32T } } ,
{ " auto_tuned " ,
{ offsetof ( struct GenericRateLimiter : : GenericRateLimiterOptions ,
auto_tuned ) ,
OptionType : : kBoolean } } ,
{ " clock " ,
OptionTypeInfo : : AsCustomSharedPtr < SystemClock > (
offsetof ( struct GenericRateLimiter : : GenericRateLimiterOptions ,
clock ) ,
OptionVerificationType : : kByNameAllowFromNull ,
OptionTypeFlags : : kAllowNull ) } ,
# endif // ROCKSDB_LITE
} ;
GenericRateLimiter : : GenericRateLimiter (
int64_t rate_bytes_per_sec , int64_t refill_period_us , int32_t fairness ,
RateLimiter : : Mode mode , const std : : shared_ptr < SystemClock > & clock ,
bool auto_tuned )
: RateLimiter ( mode ) ,
options_ ( rate_bytes_per_sec , refill_period_us , fairness , clock ,
auto_tuned ) ,
refill_period_us_ ( refill_period_us ) ,
rate_bytes_per_sec_ ( auto_tuned ? rate_bytes_per_sec / 2
: rate_bytes_per_sec ) ,
refill_bytes_per_period_ (
CalculateRefillBytesPerPeriod ( rate_bytes_per_sec_ ) ) ,
clock_ ( clock ) ,
stop_ ( false ) ,
exit_cv_ ( & request_mutex_ ) ,
requests_to_wait_ ( 0 ) ,
available_bytes_ ( 0 ) ,
next_refill_us_ ( NowMicrosMonotonic ( ) ) ,
fairness_ ( fairness > 100 ? 100 : fairness ) ,
rnd_ ( ( uint32_t ) time ( nullptr ) ) ,
wait_until_refill_pending_ ( false ) ,
num_drains_ ( 0 ) {
RegisterOptions ( & options_ , & generic_rate_limiter_type_info ) ;
auto_tuned_ ( auto_tuned ) ,
num_drains_ ( 0 ) ,
max_bytes_per_sec_ ( rate_bytes_per_sec ) ,
tuned_time_ ( NowMicrosMonotonic ( ) ) {
for ( int i = Env : : IO_LOW ; i < Env : : IO_TOTAL ; + + i ) {
total_requests_ [ i ] = 0 ;
total_bytes_through_ [ i ] = 0 ;
}
Initialize ( ) ;
}
void GenericRateLimiter : : Initialize ( ) {
if ( options_ . clock = = nullptr ) {
options_ . clock = SystemClock : : Default ( ) ;
}
options_ . fairness = std : : min ( options_ . fairness , 100 ) ;
next_refill_us_ = NowMicrosMonotonic ( ) ;
tuned_time_ = std : : chrono : : microseconds ( NowMicrosMonotonic ( ) ) ;
if ( options_ . auto_tuned ) {
rate_bytes_per_sec_ = options_ . max_bytes_per_sec / 2 ;
} else {
rate_bytes_per_sec_ = options_ . max_bytes_per_sec ;
}
refill_bytes_per_period_ = CalculateRefillBytesPerPeriod ( rate_bytes_per_sec_ ) ;
}
GenericRateLimiter : : ~ GenericRateLimiter ( ) {
@ -135,18 +95,6 @@ GenericRateLimiter::~GenericRateLimiter() {
}
}
Status GenericRateLimiter : : PrepareOptions ( const ConfigOptions & options ) {
if ( options_ . fairness < = 0 ) {
return Status : : InvalidArgument ( " Fairness must be > 0 " ) ;
} else if ( options_ . max_bytes_per_sec < = 0 ) {
return Status : : InvalidArgument ( " max_bytes_per_sec must be > 0 " ) ;
} else if ( options_ . refill_period_us < = 0 ) {
return Status : : InvalidArgument ( " Refill_period_us must be > 0 " ) ;
}
Initialize ( ) ;
return RateLimiter : : PrepareOptions ( options ) ;
}
// This API allows user to dynamically change rate limiter's bytes per second.
void GenericRateLimiter : : SetBytesPerSecond ( int64_t bytes_per_second ) {
assert ( bytes_per_second > 0 ) ;
@ -165,11 +113,11 @@ void GenericRateLimiter::Request(int64_t bytes, const Env::IOPriority pri,
& rate_bytes_per_sec_ ) ;
MutexLock g ( & request_mutex_ ) ;
if ( options_ . auto_tuned ) {
if ( auto_tuned_ ) {
static const int kRefillsPerTune = 100 ;
std : : chrono : : microseconds now ( NowMicrosMonotonic ( ) ) ;
if ( now - tuned_time_ > = kRefillsPerTune * std : : chrono : : microseconds (
options_ . refill_period_us ) ) {
if ( now - tuned_time_ > =
kRefillsPerTune * std : : chrono : : microseconds ( refill_period_us_ ) ) {
Status s = Tune ( ) ;
s . PermitUncheckedError ( ) ; //**TODO: What to do on error?
}
@ -213,7 +161,7 @@ void GenericRateLimiter::Request(int64_t bytes, const Env::IOPriority pri,
} else {
// Whichever thread reaches here first performs duty (1) as described
// above.
int64_t wait_until = options_ . clock - > NowMicros ( ) + time_until_refill_us ;
int64_t wait_until = clock_ - > NowMicros ( ) + time_until_refill_us ;
RecordTick ( stats , NUMBER_RATE_LIMITER_DRAINS ) ;
+ + num_drains_ ;
wait_until_refill_pending_ = true ;
@ -273,12 +221,12 @@ GenericRateLimiter::GeneratePriorityIterationOrder() {
// first
pri_iteration_order [ 0 ] = Env : : IO_USER ;
bool high_pri_iterated_after_mid_low_pri = rnd_ . OneIn ( options_ . fairness ) ;
bool high_pri_iterated_after_mid_low_pri = rnd_ . OneIn ( fairness_ ) ;
TEST_SYNC_POINT_CALLBACK (
" GenericRateLimiter::GeneratePriorityIterationOrder:: "
" PostRandomOneInFairnessForHighPri " ,
& high_pri_iterated_after_mid_low_pri ) ;
bool mid_pri_itereated_after_low_pri = rnd_ . OneIn ( options_ . fairness ) ;
bool mid_pri_itereated_after_low_pri = rnd_ . OneIn ( fairness_ ) ;
TEST_SYNC_POINT_CALLBACK (
" GenericRateLimiter::GeneratePriorityIterationOrder:: "
" PostRandomOneInFairnessForMidPri " ,
@ -307,7 +255,7 @@ GenericRateLimiter::GeneratePriorityIterationOrder() {
void GenericRateLimiter : : RefillBytesAndGrantRequests ( ) {
TEST_SYNC_POINT ( " GenericRateLimiter::RefillBytesAndGrantRequests " ) ;
next_refill_us_ = NowMicrosMonotonic ( ) + options_ . refill_period_us ;
next_refill_us_ = NowMicrosMonotonic ( ) + refill_period_us_ ;
// Carry over the left over quota from the last period
auto refill_bytes_per_period =
refill_bytes_per_period_ . load ( std : : memory_order_relaxed ) ;
@ -348,12 +296,12 @@ void GenericRateLimiter::RefillBytesAndGrantRequests() {
int64_t GenericRateLimiter : : CalculateRefillBytesPerPeriod (
int64_t rate_bytes_per_sec ) {
if ( std : : numeric_limits < int64_t > : : max ( ) / rate_bytes_per_sec <
options_ . refill_period_us ) {
refill_period_us_ ) {
// Avoid unexpected result in the overflow case. The result now is still
// inaccurate but is a number that is large enough.
return std : : numeric_limits < int64_t > : : max ( ) / 1000000 ;
} else {
return rate_bytes_per_sec * options_ . refill_period_us / 1000000 ;
return rate_bytes_per_sec * refill_period_us_ / 1000000 ;
}
}
@ -368,11 +316,10 @@ Status GenericRateLimiter::Tune() {
std : : chrono : : microseconds prev_tuned_time = tuned_time_ ;
tuned_time_ = std : : chrono : : microseconds ( NowMicrosMonotonic ( ) ) ;
int64_t elapsed_intervals =
( tuned_time_ - prev_tuned_time +
std : : chrono : : microseconds ( options_ . refill_period_us ) -
std : : chrono : : microseconds ( 1 ) ) /
std : : chrono : : microseconds ( options_ . refill_period_us ) ;
int64_t elapsed_intervals = ( tuned_time_ - prev_tuned_time +
std : : chrono : : microseconds ( refill_period_us_ ) -
std : : chrono : : microseconds ( 1 ) ) /
std : : chrono : : microseconds ( refill_period_us_ ) ;
// We tune every kRefillsPerTune intervals, so the overflow and division-by-
// zero conditions should never happen.
assert ( num_drains_ < = std : : numeric_limits < int64_t > : : max ( ) / 100 ) ;
@ -382,13 +329,13 @@ Status GenericRateLimiter::Tune() {
int64_t prev_bytes_per_sec = GetBytesPerSecond ( ) ;
int64_t new_bytes_per_sec ;
if ( drained_pct = = 0 ) {
new_bytes_per_sec = options_ . max_bytes_per_sec / kAllowedRangeFactor ;
new_bytes_per_sec = max_bytes_per_sec_ / kAllowedRangeFactor ;
} else if ( drained_pct < kLowWatermarkPct ) {
// sanitize to prevent overflow
int64_t sanitized_prev_bytes_per_sec =
std : : min ( prev_bytes_per_sec , std : : numeric_limits < int64_t > : : max ( ) / 100 ) ;
new_bytes_per_sec =
std : : max ( options_ . max_bytes_per_sec / kAllowedRangeFactor ,
std : : max ( max_bytes_per_sec_ / kAllowedRangeFactor ,
sanitized_prev_bytes_per_sec * 100 / ( 100 + kAdjustFactorPct ) ) ;
} else if ( drained_pct > kHighWatermarkPct ) {
// sanitize to prevent overflow
@ -396,7 +343,7 @@ Status GenericRateLimiter::Tune() {
std : : min ( prev_bytes_per_sec , std : : numeric_limits < int64_t > : : max ( ) /
( 100 + kAdjustFactorPct ) ) ;
new_bytes_per_sec =
std : : min ( options_ . max_bytes_per_sec ,
std : : min ( max_bytes_per_sec_ ,
sanitized_prev_bytes_per_sec * ( 100 + kAdjustFactorPct ) / 100 ) ;
} else {
new_bytes_per_sec = prev_bytes_per_sec ;
@ -419,79 +366,7 @@ RateLimiter* NewGenericRateLimiter(
std : : unique_ptr < RateLimiter > limiter (
new GenericRateLimiter ( rate_bytes_per_sec , refill_period_us , fairness ,
mode , SystemClock : : Default ( ) , auto_tuned ) ) ;
Status s = limiter - > PrepareOptions ( ConfigOptions ( ) ) ;
if ( s . ok ( ) ) {
return limiter . release ( ) ;
} else {
assert ( false ) ;
return nullptr ;
}
}
namespace {
# ifndef ROCKSDB_LITE
static int RegisterBuiltinRateLimiters ( ObjectLibrary & library ,
const std : : string & /*arg*/ ) {
library . AddFactory < RateLimiter > (
GenericRateLimiter : : kClassName ( ) ,
[ ] ( const std : : string & /*uri*/ , std : : unique_ptr < RateLimiter > * guard ,
std : : string * /*errmsg*/ ) {
guard - > reset (
new GenericRateLimiter ( std : : numeric_limits < int64_t > : : max ( ) ) ) ;
return guard - > get ( ) ;
} ) ;
size_t num_types ;
return static_cast < int > ( library . GetFactoryCount ( & num_types ) ) ;
}
static std : : unordered_map < std : : string , RateLimiter : : Mode >
rate_limiter_mode_map = {
{ " kReadsOnly " , RateLimiter : : Mode : : kReadsOnly } ,
{ " kWritesOnly " , RateLimiter : : Mode : : kWritesOnly } ,
{ " kAllIo " , RateLimiter : : Mode : : kAllIo } ,
} ;
# endif // ROCKSDB_LITE
static bool LoadRateLimiter ( const std : : string & name ,
std : : shared_ptr < RateLimiter > * limiter ) {
auto plen = strlen ( GenericRateLimiter : : kClassName ( ) ) ;
if ( name . size ( ) > plen + 2 & & name [ plen ] = = ' : ' & &
StartsWith ( name , GenericRateLimiter : : kClassName ( ) ) ) {
auto rate = ParseInt64 ( name . substr ( plen + 1 ) ) ;
limiter - > reset ( new GenericRateLimiter ( rate ) ) ;
return true ;
} else {
return false ;
}
}
static std : : unordered_map < std : : string , OptionTypeInfo > rate_limiter_type_info =
{
# ifndef ROCKSDB_LITE
{ " mode " ,
OptionTypeInfo : : Enum < RateLimiter : : Mode > ( 0 , & rate_limiter_mode_map ) } ,
# endif // ROCKSDB_LITE
} ;
} // namespace
RateLimiter : : RateLimiter ( Mode mode ) : mode_ ( mode ) {
RegisterOptions ( " " , & mode_ , & rate_limiter_type_info ) ;
}
Status RateLimiter : : CreateFromString ( const ConfigOptions & config_options ,
const std : : string & value ,
std : : shared_ptr < RateLimiter > * result ) {
if ( value . empty ( ) ) {
result - > reset ( ) ;
return Status : : OK ( ) ;
} else {
# ifndef ROCKSDB_LITE
static std : : once_flag once ;
std : : call_once ( once , [ & ] ( ) {
RegisterBuiltinRateLimiters ( * ( ObjectLibrary : : Default ( ) . get ( ) ) , " " ) ;
} ) ;
# endif // ROCKSDB_LITE
return LoadSharedObject < RateLimiter > ( config_options , value , LoadRateLimiter ,
result ) ;
}
return limiter . release ( ) ;
}
} // namespace ROCKSDB_NAMESPACE