external/pg_stat_monitor
1
0
Fork 0
mirror of https://github.com/percona/pg_stat_monitor.git synced 2026-02-04 14:06:20 +00:00
Code Issues Packages Projects Releases Wiki Activity

PG-154: Add backup option in case of no space left in the bucket.

Browse Source
This commit is contained in:
Ibrar Ahmed
2020-11-29 20:11:23 +00:00
parent 75bafcb590
commit bedc2ffc78
4 changed files with 251 additions and 83 deletions
Download Patch File Download Diff File Expand all files Collapse all files

154
pg_stat_monitor.c
View File

@@ -16,7 +16,9 @@
PG_MODULE_MAGIC;
#define BUILD_VERSION "0.6.0"
#define BUILD_VERSION "0.6.0"
#define PG_STAT_STATEMENTS_COLS 41 /* maximum of above */
#define PGSM_TEXT_FILE "/tmp/pg_stat_monitor_query"
/*---- Initicalization Function Declarations ----*/
void _PG_init(void);
@@ -32,13 +34,14 @@ static int plan_nested_level = 0;
static int exec_nested_level = 0;
#endif
FILE *qfile;
static bool system_init = false;
static struct rusage rusage_start;
static struct rusage rusage_end;
static unsigned char *pgss_qbuf[MAX_BUCKETS];
static bool IsSystemInitialized(void);
static void dump_queries_buffer(int bucket_id, unsigned char *buf, int buf_len);
/* Saved hook values in case of unload */
static planner_hook_type planner_hook_next = NULL;
@@ -53,7 +56,6 @@ void pgsm_emit_log_hook(ErrorData *edata);
static shmem_startup_hook_type prev_shmem_startup_hook = NULL;
static ExecutorCheckPerms_hook_type prev_ExecutorCheckPerms_hook = NULL;
PG_FUNCTION_INFO_V1(pg_stat_monitor_version);
PG_FUNCTION_INFO_V1(pg_stat_monitor_reset);
PG_FUNCTION_INFO_V1(pg_stat_monitor_1_2);
@@ -130,8 +132,9 @@ static int comp_location(const void *a, const void *b);
static uint64 get_next_wbucket(pgssSharedState *pgss);
static void store_query(uint64 queryid, const char *query, uint64 query_len);
static uint64 locate_query(uint64 bucket_id, uint64 queryid, char * query);
static void store_query(int bucket_id, uint64 queryid, const char *query, uint64 query_len);
static uint64 read_query(unsigned char *buf, uint64 queryid, char * query);
int read_query_buffer(int bucket_id, uint64 queryid, char *query_txt);
static uint64 get_query_id(pgssJumbleState *jstate, Query *query);
@@ -141,6 +144,8 @@ static uint64 get_query_id(pgssJumbleState *jstate, Query *query);
void
_PG_init(void)
{
int i;
elog(DEBUG2, "pg_stat_monitor: %s()", __FUNCTION__);
/*
* In order to create our shared memory area, we have to be loaded via
@@ -156,6 +161,13 @@ _PG_init(void)
/* Inilize the GUC variables */
init_guc();
for (i = 0; i < PGSM_MAX_BUCKETS; i++)
{
char file_name[1024];
sprintf(file_name, "%s.%d", PGSM_TEXT_FILE, i);
unlink(file_name);
}
EmitWarningsOnPlaceholders("pg_stat_monitor");
/*
@@ -233,7 +245,6 @@ pg_stat_monitor_version(PG_FUNCTION_ARGS)
PG_RETURN_TEXT_P(cstring_to_text(BUILD_VERSION));
}
#define PG_STAT_STATEMENTS_COLS 41 /* maximum of above */
/*
* Post-parse-analysis hook: mark query with a queryId
@@ -660,7 +671,7 @@ pgss_hash_string(const char *str, int len)
static PgBackendStatus*
pg_get_backend_status(void)
{
LocalPgBackendStatus *local_beentry;
LocalPgBackendStatus *local_beentry;
int num_backends = pgstat_fetch_stat_numbackends();
int i;
@@ -861,9 +872,9 @@ static void pgss_store(uint64 queryId,
goto exit;
}
if (PGSM_NORMALIZED_QUERY)
store_query(queryId, norm_query ? norm_query : query, query_len);
store_query(key.bucket_id, queryId, norm_query ? norm_query : query, query_len);
else
store_query(queryId, query, query_len);
store_query(key.bucket_id, queryId, query, query_len);
}
/*
@@ -1090,9 +1101,20 @@ pg_stat_monitor_internal(FunctionCallInfo fcinfo,
memset(values, 0, sizeof(values));
memset(nulls, 0, sizeof(nulls));
if(locate_query(entry->key.bucket_id, queryid, query_txt) == 0)
query_txt = NULL;
if (!hash_find_query_entry(entry->key.bucket_id, queryid))
{
sprintf(query_txt, "%s", "pg_stat_monitor: queryid not found in hash and in temporay file");
}
else
{
unsigned char *buf = pgss_qbuf[entry->key.bucket_id];
if(read_query(buf, queryid, query_txt) == 0)
{
len = read_query_buffer(entry->key.bucket_id, queryid, query_txt);
if (len != MAX_QUERY_BUFFER_BUCKET)
sprintf(query_txt, "%s", "pg_stat_monitor: query not found either in hash nor in temporay file");
}
}
if (query_txt)
sprintf(queryid_txt, "%08lX", queryid);
else
@@ -1213,8 +1235,9 @@ static uint64
get_next_wbucket(pgssSharedState *pgss)
{
struct timeval tv;
uint64 current_usec;
uint64 bucket_id;
uint64 current_usec;
uint64 bucket_id;
char file_name[1024];
gettimeofday(&tv,NULL);
current_usec = tv.tv_sec;
@@ -1229,6 +1252,11 @@ get_next_wbucket(pgssSharedState *pgss)
LWLockAcquire(pgss->lock, LW_EXCLUSIVE);
buf = pgss_qbuf[bucket_id];
hash_entry_dealloc(bucket_id);
hash_query_entry_dealloc(bucket_id);
sprintf(file_name, "%s.%d", PGSM_TEXT_FILE, (int)bucket_id);
unlink(file_name);
printf("\nRemove file %s\n", file_name);
/* reset the query buffer */
memset(buf, 0, sizeof (uint64));
LWLockRelease(pgss->lock);
@@ -2199,17 +2227,16 @@ intarray_get_datum(int32 arr[], int len)
}
static uint64
locate_query(uint64 bucket_id, uint64 queryid, char * query)
read_query(unsigned char *buf, uint64 queryid, char * query)
{
bool found = false;
uint64 query_id = 0;
uint64 query_len = 0;
uint64 rlen = 0;
uint64 buf_len = 0;
unsigned char *buf = pgss_qbuf[bucket_id];
memcpy(&buf_len, buf, sizeof (uint64));
if (buf_len <= sizeof (uint64))
if (buf_len <= 0)
return 0;
rlen = sizeof (uint64); /* Move forwad to skip length bytes */
@@ -2246,7 +2273,7 @@ locate_query(uint64 bucket_id, uint64 queryid, char * query)
}
static void
store_query(uint64 queryid, const char *query, uint64 query_len)
store_query(int bucket_id, uint64 queryid, const char *query, uint64 query_len)
{
uint64 buf_len = 0;
pgssSharedState *pgss = pgsm_get_ss();
@@ -2258,18 +2285,20 @@ store_query(uint64 queryid, const char *query, uint64 query_len)
/* Already have query in the shared buffer, there
* is no need to add that again.
*/
if (locate_query(pgss->current_wbucket, queryid, NULL) == queryid)
if (hash_find_query_entry(bucket_id, queryid))
return;
if (!hash_create_query_entry(bucket_id, queryid))
return;
memcpy(&buf_len, buf, sizeof (uint64));
if (buf_len == 0)
buf_len += sizeof (uint64);
if ((buf_len + query_len + sizeof(uint64) + sizeof(uint64)) > pgsm_get_bucket_size())
if (QUERY_BUFFER_OVERFLOW(buf_len, query_len))
{
/* Buffer is full */
elog(INFO, "pg_stat_monitor: no space left in shared_buffer");
return;
dump_queries_buffer(bucket_id, buf, MAX_QUERY_BUFFER_BUCKET);
buf_len = sizeof (uint64);
}
memcpy(&buf[buf_len], &queryid, sizeof (uint64)); /* query id */
@@ -2417,7 +2446,11 @@ pg_stat_monitor_settings(PG_FUNCTION_ARGS)
MemoryContextSwitchTo(oldcontext);
#if PG_VERSION_NUM >= 130000
for(i = 0; i < 11; i++)
#else
for(i = 0; i < 10; i++)
#endif
{
Datum values[7];
bool nulls[7];
@@ -2490,3 +2523,78 @@ IsSystemInitialized(void)
return (system_init && IsHashInitialize());
}
static void
dump_queries_buffer(int bucket_id, unsigned char *buf, int buf_len)
{
int fd = 0;
char file_name[1024];
sprintf(file_name, "%s.%d", PGSM_TEXT_FILE, bucket_id);
printf("\nWriting to %s\n", file_name);
fd = OpenTransientFile(file_name, O_RDWR | O_CREAT | O_APPEND | PG_BINARY);
if (fd < 0)
ereport(LOG,
(errcode_for_file_access(),
errmsg("could not write file \"%s\": %m",
file_name)));
if (write(fd, buf, buf_len) != buf_len)
ereport(LOG,
(errcode_for_file_access(),
errmsg("could not write file \"%s\": %m",
file_name)));
if (fd > 0)
CloseTransientFile(fd);
}
int
read_query_buffer(int bucket_id, uint64 queryid, char *query_txt)
{
int fd = 0;
int buf_len;
char file_name[1024];
unsigned char *buf = NULL;
int off = 0;
sprintf(file_name, "%s.%d", PGSM_TEXT_FILE, bucket_id);
fd = OpenTransientFile(file_name, O_RDONLY | PG_BINARY);
if (fd < 0)
goto exit;
buf = (unsigned char*) palloc(MAX_QUERY_BUFFER_BUCKET);
for(;;)
{
if (lseek(fd, off, SEEK_SET) != off)
goto exit;
buf_len = read(fd, buf, MAX_QUERY_BUFFER_BUCKET);
if (buf_len != MAX_QUERY_BUFFER_BUCKET)
{
if (errno != ENOENT)
goto exit;
if (buf_len == 0)
break;
}
off += buf_len;
if (read_query(buf, queryid, query_txt))
break;
}
if (fd > 0)
CloseTransientFile(fd);
if (buf)
pfree(buf);
return buf_len;
exit:
ereport(LOG,
(errcode_for_file_access(),
errmsg("could not read file \"%s\": %m",
file_name)));
if (fd > 0)
CloseTransientFile(fd);
if (buf)
pfree(buf);
return buf_len;
}