pg_stat_monitor/pg_stat_monitor.h

521 lines
16 KiB
C

/*-------------------------------------------------------------------------
*
* pg_stat_monitor.h
* Track statement execution times across a whole database cluster.
*
* Portions Copyright © 2018-2020, Percona LLC and/or its affiliates
*
* Portions Copyright (c) 1996-2020, PostgreSQL Global Development Group
*
* Portions Copyright (c) 1994, The Regents of the University of California
*
* IDENTIFICATION
* contrib/pg_stat_monitor/pg_stat_monitor.h
*
*-------------------------------------------------------------------------
*/
#ifndef __PG_STAT_MONITOR_H__
#define __PG_STAT_MONITOR_H__
#include "postgres.h"
#include <arpa/inet.h>
#include <math.h>
#include <sys/stat.h>
#include <unistd.h>
#include <time.h>
#include <sys/time.h>
#include <sys/resource.h>
#include "access/hash.h"
#include "catalog/pg_authid.h"
#include "executor/instrument.h"
#include "common/ip.h"
#include "funcapi.h"
#include "access/twophase.h"
#include "mb/pg_wchar.h"
#include "miscadmin.h"
#include "optimizer/planner.h"
#include "postmaster/bgworker.h"
#include "parser/analyze.h"
#include "parser/parsetree.h"
#include "parser/scanner.h"
#include "parser/scansup.h"
#include "pgstat.h"
#include "storage/fd.h"
#include "storage/ipc.h"
#include "storage/spin.h"
#include "tcop/utility.h"
#include "utils/acl.h"
#include "utils/builtins.h"
#include "utils/memutils.h"
#include "utils/timestamp.h"
#include "utils/lsyscache.h"
#include "utils/guc.h"
#include "utils/guc_tables.h"
#define MAX_BACKEND_PROCESES (MaxBackends + NUM_AUXILIARY_PROCS + max_prepared_xacts)
#define IntArrayGetTextDatum(x,y) intarray_get_datum(x,y)
/* XXX: Should USAGE_EXEC reflect execution time and/or buffer usage? */
#define USAGE_EXEC(duration) (1.0)
#define USAGE_INIT (1.0) /* including initial planning */
#define ASSUMED_MEDIAN_INIT (10.0) /* initial assumed median usage */
#define ASSUMED_LENGTH_INIT 1024 /* initial assumed mean query length */
#define USAGE_DECREASE_FACTOR (0.99) /* decreased every entry_dealloc */
#define STICKY_DECREASE_FACTOR (0.50) /* factor for sticky entries */
#define USAGE_DEALLOC_PERCENT 5 /* free this % of entries at once */
#define JUMBLE_SIZE 1024 /* query serialization buffer size */
#define MAX_RESPONSE_BUCKET 50
#define INVALID_BUCKET_ID -1
#define MAX_REL_LEN 255
#define MAX_BUCKETS 10
#define TEXT_LEN 255
#define ERROR_MESSAGE_LEN 100
#define REL_LST 10
#define REL_LEN 1000
#define CMD_LST 10
#define CMD_LEN 20
#define APPLICATIONNAME_LEN 100
#define COMMENTS_LEN 512
#define PGSM_OVER_FLOW_MAX 10
#define PLAN_TEXT_LEN 1024
/* the assumption of query max nested level */
#define DEFAULT_MAX_NESTED_LEVEL 10
#define MAX_QUERY_BUF (PGSM_QUERY_SHARED_BUFFER * 1024 * 1024)
#define MAX_BUCKETS_MEM (PGSM_MAX * 1024 * 1024)
#define BUCKETS_MEM_OVERFLOW() ((hash_get_num_entries(pgss_hash) * sizeof(pgssEntry)) >= MAX_BUCKETS_MEM)
#define MAX_BUCKET_ENTRIES (MAX_BUCKETS_MEM / sizeof(pgssEntry))
#define QUERY_BUFFER_OVERFLOW(x,y) ((x + y + sizeof(uint64) + sizeof(uint64)) > MAX_QUERY_BUF)
#define QUERY_MARGIN 100
#define MIN_QUERY_LEN 10
#define SQLCODE_LEN 20
#if PG_VERSION_NUM >= 130000
#define MAX_SETTINGS 15
#else
#define MAX_SETTINGS 14
#endif
/* Update this if need a enum GUC with more options. */
#define MAX_ENUM_OPTIONS 6
typedef struct GucVariables
{
enum config_type type; /* PGC_BOOL, PGC_INT, PGC_REAL, PGC_STRING, PGC_ENUM */
int guc_variable;
char guc_name[TEXT_LEN];
char guc_desc[TEXT_LEN];
int guc_default;
int guc_min;
int guc_max;
int guc_unit;
int *guc_value;
bool guc_restart;
int n_options;
char guc_options[MAX_ENUM_OPTIONS][32];
} GucVariable;
#if PG_VERSION_NUM < 130000
typedef struct WalUsage
{
long wal_records; /* # of WAL records produced */
long wal_fpi; /* # of WAL full page images produced */
uint64 wal_bytes; /* size of WAL records produced */
} WalUsage;
#endif
typedef enum OVERFLOW_TARGET
{
OVERFLOW_TARGET_NONE = 0,
OVERFLOW_TARGET_DISK
} OVERFLOW_TARGET;
typedef enum pgssStoreKind
{
PGSS_INVALID = -1,
/*
* PGSS_PLAN and PGSS_EXEC must be respectively 0 and 1 as they're used to
* reference the underlying values in the arrays in the Counters struct,
* and this order is required in pg_stat_statements_internal().
*/
PGSS_PARSE = 0,
PGSS_PLAN,
PGSS_EXEC,
PGSS_FINISHED,
PGSS_ERROR,
PGSS_NUMKIND /* Must be last value of this enum */
} pgssStoreKind;
/* the assumption of query max nested level */
#define DEFAULT_MAX_NESTED_LEVEL 10
/*
* Type of aggregate keys
*/
typedef enum AGG_KEY
{
AGG_KEY_DATABASE = 0,
AGG_KEY_USER,
AGG_KEY_HOST
} AGG_KEY;
#define MAX_QUERY_LEN 1024
/* shared memory storage for the query */
typedef struct CallTime
{
double total_time; /* total execution time, in msec */
double min_time; /* minimum execution time in msec */
double max_time; /* maximum execution time in msec */
double mean_time; /* mean execution time in msec */
double sum_var_time; /* sum of variances in execution time in msec */
} CallTime;
/*
* Entry type for queries hash table (query ID).
*
* We use a hash table to keep track of query IDs that have their
* corresponding query text added to the query buffer (pgsm_query_shared_buffer).
*
* This allow us to avoid adding duplicated queries to the buffer, therefore
* leaving more space for other queries and saving some CPU.
*/
typedef struct pgssQueryEntry
{
uint64 queryid; /* query identifier, also the key. */
size_t query_pos; /* query location within query buffer */
} pgssQueryEntry;
typedef struct PlanInfo
{
uint64 planid; /* plan identifier */
char plan_text[PLAN_TEXT_LEN]; /* plan text */
size_t plan_len; /* strlen(plan_text) */
} PlanInfo;
typedef struct pgssHashKey
{
uint64 bucket_id; /* bucket number */
uint64 queryid; /* query identifier */
uint64 userid; /* user OID */
uint64 dbid; /* database OID */
uint64 ip; /* client ip address */
uint64 planid; /* plan identifier */
uint64 appid; /* hash of application name */
uint64 toplevel; /* query executed at top level */
} pgssHashKey;
typedef struct QueryInfo
{
uint64 parentid; /* parent queryid of current query*/
int64 type; /* type of query, options are query, info, warning, error, fatal */
char application_name[APPLICATIONNAME_LEN];
char comments[COMMENTS_LEN];
char relations[REL_LST][REL_LEN]; /* List of relation involved in the query */
int num_relations; /* Number of relation in the query */
CmdType cmd_type; /* query command type SELECT/UPDATE/DELETE/INSERT */
} QueryInfo;
typedef struct ErrorInfo
{
int64 elevel; /* error elevel */
char sqlcode[SQLCODE_LEN]; /* error sqlcode */
char message[ERROR_MESSAGE_LEN]; /* error message text */
} ErrorInfo;
typedef struct Calls
{
int64 calls; /* # of times executed */
int64 rows; /* total # of retrieved or affected rows */
double usage; /* usage factor */
} Calls;
typedef struct Blocks
{
int64 shared_blks_hit; /* # of shared buffer hits */
int64 shared_blks_read; /* # of shared disk blocks read */
int64 shared_blks_dirtied; /* # of shared disk blocks dirtied */
int64 shared_blks_written; /* # of shared disk blocks written */
int64 local_blks_hit; /* # of local buffer hits */
int64 local_blks_read; /* # of local disk blocks read */
int64 local_blks_dirtied; /* # of local disk blocks dirtied */
int64 local_blks_written; /* # of local disk blocks written */
int64 temp_blks_read; /* # of temp blocks read */
int64 temp_blks_written; /* # of temp blocks written */
double blk_read_time; /* time spent reading, in msec */
double blk_write_time; /* time spent writing, in msec */
} Blocks;
typedef struct SysInfo
{
float utime; /* user cpu time */
float stime; /* system cpu time */
} SysInfo;
typedef struct Wal_Usage
{
int64 wal_records; /* # of WAL records generated */
int64 wal_fpi; /* # of WAL full page images generated */
uint64 wal_bytes; /* total amount of WAL bytes generated */
} Wal_Usage;
typedef struct Counters
{
uint64 bucket_id; /* bucket id */
Calls calls;
QueryInfo info;
CallTime time;
Calls plancalls;
CallTime plantime;
PlanInfo planinfo;
Blocks blocks;
SysInfo sysinfo;
ErrorInfo error;
Wal_Usage walusage;
int resp_calls[MAX_RESPONSE_BUCKET]; /* execution time's in msec */
uint64 state; /* query state */
} Counters;
/* Some global structure to get the cpu usage, really don't like the idea of global variable */
/*
* Statistics per statement
*/
typedef struct pgssEntry
{
pgssHashKey key; /* hash key of entry - MUST BE FIRST */
Counters counters; /* the statistics for this query */
int encoding; /* query text encoding */
slock_t mutex; /* protects the counters only */
size_t query_pos; /* query location within query buffer */
} pgssEntry;
/*
* Global shared state
*/
typedef struct pgssSharedState
{
LWLock *lock; /* protects hashtable search/modification */
double cur_median_usage; /* current median usage in hashtable */
slock_t mutex; /* protects following fields only: */
Size extent; /* current extent of query file */
int64 n_writers; /* number of active writers to query file */
pg_atomic_uint64 current_wbucket;
pg_atomic_uint64 prev_bucket_sec;
uint64 bucket_entry[MAX_BUCKETS];
char bucket_start_time[MAX_BUCKETS][60]; /* start time of the bucket */
LWLock *errors_lock; /* protects errors hashtable search/modification */
/*
* These variables are used when pgsm_overflow_target is ON.
*
* overflow is set to true when the query buffer overflows.
*
* n_bucket_cycles counts the number of times we changed bucket
* since the query buffer overflowed. When it reaches pgsm_max_buckets
* we remove the dump file, also reset the counter.
*
* This allows us to avoid having a large file on disk that would also
* slowdown queries to the pg_stat_monitor view.
*/
bool overflow;
size_t n_bucket_cycles;
} pgssSharedState;
#define ResetSharedState(x) \
do { \
x->cur_median_usage = ASSUMED_MEDIAN_INIT; \
x->cur_median_usage = ASSUMED_MEDIAN_INIT; \
x->n_writers = 0; \
pg_atomic_init_u64(&x->current_wbucket, 0); \
pg_atomic_init_u64(&x->prev_bucket_sec, 0); \
memset(&x->bucket_entry, 0, MAX_BUCKETS * sizeof(uint64)); \
} while(0)
#if PG_VERSION_NUM < 140000
/*
* Struct for tracking locations/lengths of constants during normalization
*/
typedef struct LocationLen
{
int location; /* start offset in query text */
int length; /* length in bytes, or -1 to ignore */
} LocationLen;
/*
* Working state for computing a query jumble and producing a normalized
* query string
*/
typedef struct JumbleState
{
/* Jumble of current query tree */
unsigned char *jumble;
/* Number of bytes used in jumble[] */
Size jumble_len;
/* Array of locations of constants that should be removed */
LocationLen *clocations;
/* Allocated length of clocations array */
int clocations_buf_size;
/* Current number of valid entries in clocations array */
int clocations_count;
/* highest Param id we've seen, in order to start normalization correctly */
int highest_extern_param_id;
} JumbleState;
#endif
/* Links to shared memory state */
bool SaveQueryText(uint64 bucketid,
uint64 queryid,
unsigned char *buf,
const char *query,
uint64 query_len,
size_t *query_pos);
/* guc.c */
void init_guc(void);
GucVariable *get_conf(int i);
/* hash_create.c */
bool IsHashInitialize(void);
void pgss_shmem_startup(void);
void pgss_shmem_shutdown(int code, Datum arg);
int pgsm_get_bucket_size(void);
pgssSharedState* pgsm_get_ss(void);
HTAB *pgsm_get_plan_hash(void);
HTAB *pgsm_get_hash(void);
HTAB *pgsm_get_query_hash(void);
HTAB *pgsm_get_plan_hash(void);
void hash_entry_reset(void);
void hash_query_entryies_reset(void);
void hash_query_entries();
void hash_query_entry_dealloc(int new_bucket_id, int old_bucket_id, unsigned char *query_buffer[]);
void hash_entry_dealloc(int new_bucket_id, int old_bucket_id, unsigned char *query_buffer);
pgssEntry* hash_entry_alloc(pgssSharedState *pgss, pgssHashKey *key, int encoding);
Size hash_memsize(void);
int read_query_buffer(int bucket_id, uint64 queryid, char *query_txt, size_t pos);
uint64 read_query(unsigned char *buf, uint64 queryid, char * query, size_t pos);
void pgss_startup(void);
void set_qbuf(unsigned char *);
/* hash_query.c */
void pgss_startup(void);
/*---- GUC variables ----*/
typedef enum {
PSGM_TRACK_NONE = 0, /* track no statements */
PGSM_TRACK_TOP, /* only top level statements */
PGSM_TRACK_ALL /* all statements, including nested ones */
} PGSMTrackLevel;
static const struct config_enum_entry track_options[] =
{
{"none", PSGM_TRACK_NONE, false},
{"top", PGSM_TRACK_TOP, false},
{"all", PGSM_TRACK_ALL, false},
{NULL, 0, false}
};
#define PGSM_MAX get_conf(0)->guc_variable
#define PGSM_QUERY_MAX_LEN get_conf(1)->guc_variable
#define PGSM_TRACK_UTILITY get_conf(2)->guc_variable
#define PGSM_NORMALIZED_QUERY get_conf(3)->guc_variable
#define PGSM_MAX_BUCKETS get_conf(4)->guc_variable
#define PGSM_BUCKET_TIME get_conf(5)->guc_variable
#define PGSM_HISTOGRAM_MIN get_conf(6)->guc_variable
#define PGSM_HISTOGRAM_MAX get_conf(7)->guc_variable
#define PGSM_HISTOGRAM_BUCKETS get_conf(8)->guc_variable
#define PGSM_QUERY_SHARED_BUFFER get_conf(9)->guc_variable
#define PGSM_OVERFLOW_TARGET get_conf(10)->guc_variable
#define PGSM_QUERY_PLAN get_conf(11)->guc_variable
#define PGSM_TRACK get_conf(12)->guc_variable
#define PGSM_EXTRACT_COMMENTS get_conf(13)->guc_variable
#define PGSM_TRACK_PLANNING get_conf(14)->guc_variable
/*---- Benchmarking ----*/
#ifdef BENCHMARK
/*
* These enumerator values are used as index in the hook stats array.
* STATS_START and STATS_END are used only to delimit the range.
* STATS_END is also the length of the valid items in the enum.
*/
enum pg_hook_stats_id {
STATS_START = -1,
STATS_PGSS_POST_PARSE_ANALYZE,
STATS_PGSS_EXECUTORSTART,
STATS_PGSS_EXECUTORUN,
STATS_PGSS_EXECUTORFINISH,
STATS_PGSS_EXECUTOREND,
STATS_PGSS_PROCESSUTILITY,
#if PG_VERSION_NUM >= 130000
STATS_PGSS_PLANNER_HOOK,
#endif
STATS_PGSM_EMIT_LOG_HOOK,
STATS_PGSS_EXECUTORCHECKPERMS,
STATS_END
};
/* Hold time to execute statistics for a hook. */
struct pg_hook_stats_t {
char hook_name[64];
double min_time;
double max_time;
double total_time;
uint64 ncalls;
};
#define HOOK_STATS_SIZE MAXALIGN((size_t)STATS_END * sizeof(struct pg_hook_stats_t))
/* Allocate a pg_hook_stats_t array of size HOOK_STATS_SIZE on shared memory. */
void init_hook_stats(void);
/* Update hook time execution statistics. */
void update_hook_stats(enum pg_hook_stats_id hook_id, double time_elapsed);
/*
* Macro used to declare a hook function:
* Example:
* DECLARE_HOOK(void my_hook, const char *query, size_t length);
* Will expand to:
* static void my_hook(const char *query, size_t length);
* static void my_hook_benchmark(const char *query, size_t length);
*/
#define DECLARE_HOOK(hook, ...) \
static hook(__VA_ARGS__); \
static hook##_benchmark(__VA_ARGS__);
/*
* Macro used to wrap a hook when pg_stat_monitor is compiled with -DBENCHMARK.
*
* It is intended to be used as follows in _PG_init():
* pg_hook_function = HOOK(my_hook_function);
* Then, if pg_stat_monitor is compiled with -DBENCHMARK this will expand to:
* pg_hook_name = my_hook_function_benchmark;
* Otherwise it will simple expand to:
* pg_hook_name = my_hook_function;
*/
#define HOOK(name) name##_benchmark
#else /* #ifdef BENCHMARK */
#define DECLARE_HOOK(hook, ...) \
static hook(__VA_ARGS__);
#define HOOK(name) name
#define HOOK_STATS_SIZE 0
#endif
#endif