Add locks and convert to static shared memory

pull/6763/head
Halil Ozan Akgul 2023-03-06 16:20:42 +03:00
parent 4dfb9c6694
commit f7a479d2e4
2 changed files with 115 additions and 171 deletions

View File

@ -16,6 +16,7 @@
#include "distributed/tuplestore.h"
#include "executor/execdesc.h"
#include "storage/ipc.h"
#include "storage/lwlock.h"
#include "storage/shmem.h"
#include "utils/builtins.h"
@ -38,24 +39,20 @@ CmdType attributeCommandType = CMD_UNKNOWN;
int colocationGroupId = -1;
clock_t attributeToTenantStart = { 0 };
const char *SharedMemoryNameForMultiTenantMonitorHandleManagement =
"Shared memory handle for multi tenant monitor";
const char *SharedMemoryNameForMultiTenantMonitor =
"Shared memory for multi tenant monitor";
static shmem_startup_hook_type prev_shmem_startup_hook = NULL;
static void UpdatePeriodsIfNecessary(MultiTenantMonitor *monitor,TenantStats *tenantStats);
static void ReduceScoreIfNecessary(MultiTenantMonitor *monitor, TenantStats *tenantStats, time_t updateTime);
static void CreateMultiTenantMonitor(void);
static dsm_handle CreateSharedMemoryForMultiTenantMonitor(void);
static void StoreMultiTenantMonitorSMHandle(dsm_handle dsmHandle);
static MultiTenantMonitor * CreateSharedMemoryForMultiTenantMonitor(void);
static MultiTenantMonitor * GetMultiTenantMonitor(void);
static dsm_handle GetMultiTenantMonitorDSMHandle(void);
static void DetachSegment(void);
static void MultiTenantMonitorSMInit(void);
static dsm_handle CreateTenantStats(MultiTenantMonitor *monitor);
static dsm_handle CreateSharedMemoryForTenantStats(void);
static TenantStats * GetTenantStatsFromDSMHandle(dsm_handle dsmHandle);
static dsm_handle FindTenantStats(MultiTenantMonitor *monitor);
static int CreateTenantStats(MultiTenantMonitor *monitor);
static int FindTenantStats(MultiTenantMonitor *monitor);
static size_t MultiTenantMonitorshmemSize(void);
int MultiTenantMonitoringLogLevel = CITUS_LOG_LEVEL_OFF;
int CitusStatsTenantsPeriod = (time_t) 60;
@ -94,6 +91,8 @@ citus_stats_tenants(PG_FUNCTION_ARGS)
PG_RETURN_VOID();
}
LWLockAcquire(&monitor->lock, LW_EXCLUSIVE);
monitor->periodStart = monitor->periodStart + ((monitoringTime-monitor->periodStart)/CitusStatsTenantsPeriod)*CitusStatsTenantsPeriod;
int numberOfRowsToReturn = 0;
@ -103,7 +102,7 @@ citus_stats_tenants(PG_FUNCTION_ARGS)
}
else
{
numberOfRowsToReturn = min (monitor->tenantCount, CitusStatsTenantsLimit);
numberOfRowsToReturn = Min (monitor->tenantCount, CitusStatsTenantsLimit);
}
for (int i=0; i<numberOfRowsToReturn; i++)
@ -111,7 +110,7 @@ citus_stats_tenants(PG_FUNCTION_ARGS)
memset(values, 0, sizeof(values));
memset(isNulls, false, sizeof(isNulls));
TenantStats *tenantStats = GetTenantStatsFromDSMHandle(monitor->tenants[i]);
TenantStats *tenantStats = &monitor->tenants[i];
UpdatePeriodsIfNecessary(monitor, tenantStats);
ReduceScoreIfNecessary(monitor, tenantStats, monitoringTime);
@ -122,12 +121,13 @@ citus_stats_tenants(PG_FUNCTION_ARGS)
values[3] = Int32GetDatum(tenantStats->selectsInLastPeriod);
values[4] = Int32GetDatum(tenantStats->selectsInThisPeriod + tenantStats->insertsInThisPeriod);
values[5] = Int32GetDatum(tenantStats->selectsInLastPeriod + tenantStats->insertsInLastPeriod);
values[6] = Int64GetDatum(monitor->scores[tenantStats->rank]);
values[6] = Int64GetDatum(tenantStats->score);
tuplestore_putvalues(tupleStore, tupleDescriptor, values, isNulls);
}
LWLockRelease(&monitor->lock);
PG_RETURN_VOID();
}
@ -258,24 +258,21 @@ AttributeMetricsIfApplicable()
attributeToTenant)));
}
if (GetMultiTenantMonitorDSMHandle() == DSM_HANDLE_INVALID)
{
CreateMultiTenantMonitor();
}
MultiTenantMonitor *monitor = GetMultiTenantMonitor();
LWLockAcquire(&monitor->lock, LW_SHARED);
monitor->periodStart = monitor->periodStart + ((queryTime-monitor->periodStart)/CitusStatsTenantsPeriod)*CitusStatsTenantsPeriod;
dsm_handle tenantDSMHandle = FindTenantStats(monitor);
int tenantIndex = FindTenantStats(monitor);
if (tenantDSMHandle == DSM_HANDLE_INVALID)
if (tenantIndex == -1)
{
tenantDSMHandle = CreateTenantStats(monitor);
tenantIndex = CreateTenantStats(monitor);
}
TenantStats * tenantStats = GetTenantStatsFromDSMHandle(tenantDSMHandle);
strcpy(tenantStats->tenantAttribute, attributeToTenant);
tenantStats->colocationGroupId = colocationGroupId;
TenantStats * tenantStats = &monitor->tenants[tenantIndex];
LWLockAcquire(&tenantStats->lock, LW_EXCLUSIVE);
UpdatePeriodsIfNecessary(monitor, tenantStats);
tenantStats->lastQueryTime = queryTime;
@ -285,38 +282,25 @@ AttributeMetricsIfApplicable()
/*
* We do this after the reducing the scores so the scores in this period are not affected by the reduction.
*/
monitor->scores[tenantStats->rank] += ONE_QUERY_SCORE;
tenantStats->score += ONE_QUERY_SCORE;
/*
* After updating the score we might need to change the rank of the tenant in the monitor
*/
while(tenantStats->rank != 0 && monitor->scores[tenantStats->rank-1] < monitor->scores[tenantStats->rank])
while(tenantIndex != 0 && monitor->tenants[tenantIndex-1].score < tenantStats->score)
{
LWLockAcquire(&monitor->tenants[tenantIndex-1].lock, LW_EXCLUSIVE);
// we need to reduce previous tenants score too !!!!!!!!
TenantStats *previousTenantStats = GetTenantStatsFromDSMHandle(monitor->tenants[tenantStats->rank-1]);
elog(WARNING, "swap = %d, %d", tenantIndex, tenantIndex-1);
dsm_handle tempTenant = monitor->tenants[tenantStats->rank];
monitor->tenants[tenantStats->rank] = monitor->tenants[previousTenantStats->rank];
monitor->tenants[previousTenantStats->rank] = tempTenant;
TenantStats tempTenant = monitor->tenants[tenantIndex];
monitor->tenants[tenantIndex] = monitor->tenants[tenantIndex - 1];
monitor->tenants[tenantIndex - 1] = tempTenant;
long long tempScore = monitor->scores[tenantStats->rank];
monitor->scores[tenantStats->rank] = monitor->scores[previousTenantStats->rank];
monitor->scores[previousTenantStats->rank] = tempScore;
LWLockRelease(&monitor->tenants[tenantIndex-1].lock);
previousTenantStats->rank++;
tenantStats->rank--;
}
/*
* We keep up to CitusStatsTenantsLimit * 3 tenants instead of CitusStatsTenantsLimit,
* so we don't lose data immediately after a tenant is out of top CitusStatsTenantsLimit
*
* Every time tenant count hits CitusStatsTenantsLimit * 3, we reduce it back to CitusStatsTenantsLimit * 2.
*/
if (monitor->tenantCount >= CitusStatsTenantsLimit * 3)
{
monitor->tenantCount = CitusStatsTenantsLimit * 2;
tenantIndex--;
}
if (attributeCommandType == CMD_SELECT)
@ -332,6 +316,22 @@ AttributeMetricsIfApplicable()
tenantStats->totalInsertTime+=cpu_time_used;
}
LWLockRelease(&tenantStats->lock);
LWLockRelease(&monitor->lock);
/*
* We keep up to CitusStatsTenantsLimit * 3 tenants instead of CitusStatsTenantsLimit,
* so we don't lose data immediately after a tenant is out of top CitusStatsTenantsLimit
*
* Every time tenant count hits CitusStatsTenantsLimit * 3, we reduce it back to CitusStatsTenantsLimit * 2.
*/
if (monitor->tenantCount >= CitusStatsTenantsLimit * 3)
{
LWLockAcquire(&monitor->lock, LW_EXCLUSIVE);
monitor->tenantCount = CitusStatsTenantsLimit * 2;
LWLockRelease(&monitor->lock);
}
if (MultiTenantMonitoringLogLevel != CITUS_LOG_LEVEL_OFF)
{
ereport(NOTICE, (errmsg("total select count = %d, total CPU time = %f to tenant: %s", tenantStats->selectCount, tenantStats->totalSelectTime,
@ -410,7 +410,7 @@ ReduceScoreIfNecessary(MultiTenantMonitor *monitor, TenantStats *tenantStats, ti
*/
if (periodCountAfterLastScoreReduction > 0)
{
monitor->scores[tenantStats->rank] >>= periodCountAfterLastScoreReduction;
tenantStats->score >>= periodCountAfterLastScoreReduction;
tenantStats->lastScoreReduction = updateTime;
}
}
@ -422,9 +422,7 @@ ReduceScoreIfNecessary(MultiTenantMonitor *monitor, TenantStats *tenantStats, ti
static void
CreateMultiTenantMonitor()
{
dsm_handle dsmHandle = CreateSharedMemoryForMultiTenantMonitor();
StoreMultiTenantMonitorSMHandle(dsmHandle);
MultiTenantMonitor * monitor = GetMultiTenantMonitor();
MultiTenantMonitor * monitor = CreateSharedMemoryForMultiTenantMonitor();
monitor->tenantCount = 0;
monitor->periodStart = time(0);
}
@ -433,28 +431,26 @@ CreateMultiTenantMonitor()
/*
* CreateSharedMemoryForMultiTenantMonitor creates a dynamic shared memory segment for multi tenant monitor.
*/
static dsm_handle
static MultiTenantMonitor*
CreateSharedMemoryForMultiTenantMonitor()
{
struct dsm_segment *dsmSegment = dsm_create(sizeof(MultiTenantMonitor), DSM_CREATE_NULL_IF_MAXSEGMENTS);
dsm_pin_segment(dsmSegment);
dsm_pin_mapping(dsmSegment); // don't know why we do both !!!!!!!!!!!!!!!!!
return dsm_segment_handle(dsmSegment);
}
/*
* StoreMultiTenantMonitorSMHandle stores the dsm (dynamic shared memory) handle for multi tenant monitor
* in a non-dynamic shared memory location, so we don't lose it.
*/
static void
StoreMultiTenantMonitorSMHandle(dsm_handle dsmHandle)
{
bool found = false;
MultiTenantMonitorSMData *smData = ShmemInitStruct(SharedMemoryNameForMultiTenantMonitorHandleManagement,
sizeof(MultiTenantMonitorSMData),
MultiTenantMonitor *monitor = ShmemInitStruct(SharedMemoryNameForMultiTenantMonitor,
MultiTenantMonitorshmemSize(),
&found);
if (found)
{
return monitor;
}
smData->dsmHandle = dsmHandle;
char * trancheName = "Multi Tenant Monitor Tranche";
monitor->namedLockTranche.trancheId = LWLockNewTrancheId();
LWLockRegisterTranche(monitor->namedLockTranche.trancheId, trancheName);
LWLockInitialize(&monitor->lock, monitor->namedLockTranche.trancheId);
return monitor;
}
@ -463,54 +459,19 @@ StoreMultiTenantMonitorSMHandle(dsm_handle dsmHandle)
*/
static MultiTenantMonitor *
GetMultiTenantMonitor()
{
dsm_handle dsmHandle = GetMultiTenantMonitorDSMHandle();
if (dsmHandle == DSM_HANDLE_INVALID)
{
return NULL;
}
dsm_segment *dsmSegment = dsm_find_mapping(dsmHandle);
if (dsmSegment == NULL)
{
dsmSegment = dsm_attach(dsmHandle);
}
MultiTenantMonitor *monitor = (MultiTenantMonitor *) dsm_segment_address(dsmSegment);
dsm_pin_mapping(dsmSegment);
return monitor;
}
/*
* GetMultiTenantMonitorDSMHandle fetches the dsm (dynamic shared memory) handle for multi tenant monitor.
*/
static dsm_handle
GetMultiTenantMonitorDSMHandle()
{
bool found = false;
MultiTenantMonitorSMData *smData = ShmemInitStruct(SharedMemoryNameForMultiTenantMonitorHandleManagement,
sizeof(MultiTenantMonitorSMData),
MultiTenantMonitor *monitor = ShmemInitStruct(SharedMemoryNameForMultiTenantMonitor,
MultiTenantMonitorshmemSize(),
&found);
if (!found)
{
elog(WARNING, "dsm handle not found");
return DSM_HANDLE_INVALID;
elog(WARNING, "monitor not found");
return NULL;
}
dsm_handle dsmHandle = smData->dsmHandle;
return dsmHandle;
}
static void
DetachSegment()
{
dsm_handle dsmHandle = GetMultiTenantMonitorDSMHandle();
dsm_segment *dsmSegment = dsm_find_mapping(dsmHandle);
if (dsmSegment != NULL)
{
dsm_detach(dsmSegment);
}
return monitor;
}
@ -535,14 +496,7 @@ InitializeMultiTenantMonitorSMHandleManagement()
static void
MultiTenantMonitorSMInit()
{
bool alreadyInitialized = false;
MultiTenantMonitorSMData *smData = ShmemInitStruct(SharedMemoryNameForMultiTenantMonitorHandleManagement,
sizeof(MultiTenantMonitorSMData),
&alreadyInitialized);
if (!alreadyInitialized)
{
smData->dsmHandle = DSM_HANDLE_INVALID;
}
CreateMultiTenantMonitor();
if (prev_shmem_startup_hook != NULL)
{
@ -554,64 +508,51 @@ MultiTenantMonitorSMInit()
/*
* CreateTenantStats creates the data structure for a tenant's statistics.
*/
static dsm_handle
static int
CreateTenantStats(MultiTenantMonitor *monitor)
{
dsm_handle dsmHandle = CreateSharedMemoryForTenantStats();
monitor->tenants[monitor->tenantCount] = dsmHandle;
TenantStats *tenantStats = GetTenantStatsFromDSMHandle(dsmHandle);
tenantStats->rank = monitor->tenantCount;
int tenantIndex = monitor->tenantCount;
strcpy(monitor->tenants[tenantIndex].tenantAttribute, attributeToTenant);
monitor->tenants[tenantIndex].colocationGroupId = colocationGroupId;
char * trancheName = "Tenant Tranche";
monitor->tenants[tenantIndex].namedLockTranche.trancheId = LWLockNewTrancheId();
LWLockRegisterTranche(monitor->tenants[tenantIndex].namedLockTranche.trancheId, trancheName);
LWLockInitialize(&monitor->tenants[tenantIndex].lock, monitor->tenants[tenantIndex].namedLockTranche.trancheId);
monitor->tenantCount++;
return dsmHandle;
}
/*
* CreateSharedMemoryForTenantStats creates a dynamic shared memory segment for a tenant's statistics.
*/
static dsm_handle
CreateSharedMemoryForTenantStats()
{
struct dsm_segment *dsmSegment = dsm_create(sizeof(TenantStats), DSM_CREATE_NULL_IF_MAXSEGMENTS);
dsm_pin_segment(dsmSegment);
dsm_pin_mapping(dsmSegment); // don't know why we do both !!!!!!!!!!!!!!!!!
return dsm_segment_handle(dsmSegment);
}
/*
* GetTenantStatsFromDSMHandle returns the data structure for a tenant's statistics with the dsm (dynamic shared memory) handle.
*/
static TenantStats *
GetTenantStatsFromDSMHandle(dsm_handle dsmHandle)
{
dsm_segment *dsmSegment = dsm_find_mapping(dsmHandle);
if (dsmSegment == NULL)
{
dsmSegment = dsm_attach(dsmHandle);
}
TenantStats *stats = (TenantStats *) dsm_segment_address(dsmSegment);
dsm_pin_mapping(dsmSegment);
return stats;
return tenantIndex;
}
/*
* FindTenantStats finds the dsm (dynamic shared memory) handle for the current tenant's statistics.
*/
static dsm_handle
static int
FindTenantStats(MultiTenantMonitor *monitor)
{
for(int i=0; i<monitor->tenantCount; i++)
{
TenantStats * tenantStats = GetTenantStatsFromDSMHandle(monitor->tenants[i]);
TenantStats * tenantStats = &monitor->tenants[i];
if (strcmp(tenantStats->tenantAttribute, attributeToTenant) == 0 && tenantStats->colocationGroupId == colocationGroupId)
{
return monitor->tenants[i];
return i;
}
}
return DSM_HANDLE_INVALID;
return -1;
}
static size_t
MultiTenantMonitorshmemSize(void)
{
Size size = sizeof(MultiTenantMonitor);
size = add_size(size, mul_size(sizeof(TenantStats), CitusStatsTenantsLimit * 3));
return size;
}

View File

@ -7,15 +7,7 @@
#include "executor/execdesc.h"
#include "executor/executor.h"
typedef struct MultiTenantMonitor
{
int tenantCount;
dsm_handle tenants[300];
long long scores[300];
time_t periodStart;
} MultiTenantMonitor;
#include "storage/lwlock.h"
typedef struct TenantStats
{
@ -35,14 +27,25 @@ typedef struct TenantStats
time_t lastQueryTime;
long long score;
time_t lastScoreReduction;
int rank;
NamedLWLockTranche namedLockTranche;
LWLock lock;
} TenantStats;
typedef struct MultiTenantMonitorSMData
typedef struct MultiTenantMonitor
{
dsm_handle dsmHandle;
} MultiTenantMonitorSMData;
time_t periodStart;
NamedLWLockTranche namedLockTranche;
LWLock lock;
int tenantCount;
TenantStats tenants[FLEXIBLE_ARRAY_MEMBER];
} MultiTenantMonitor;
extern void CitusAttributeToEnd(QueryDesc *queryDesc);
extern void AttributeQueryIfAnnotated(const char *queryString, CmdType commandType);