Added functionality to return i/o statistics per process if enabled on

Linux systems.

diff --git a/pg_proctab.c b/pg_proctab.c
index 166d59329bfdc95021323400597873bffbcf3079..273fa54fac9831308e6802e6583539c88c2adf63 100644 (file)
--- a/pg_proctab.c
+++ b/pg_proctab.c
@@ -20,12 +20,29 @@
                "SELECT procpid " \
                "FROM pg_stat_activity"
 
+#ifdef __linux__
+#define GET_VALUE(value) \
+               p = strchr(p, ':'); \
+               ++p; \
+               ++p; \
+               q = strchr(p, '\n'); \
+               len = q - p; \
+               if (len >= BIGINT_LEN) \
+               { \
+                       elog(ERROR, "value is larger than the buffer: %d\n", __LINE__); \
+                       return 0; \
+               } \
+               strncpy(value, p, len); \
+               value[len] = '\0';
+#endif /* __linux__ */
+
 enum proctab {i_pid, i_comm, i_fullcomm, i_state, i_ppid, i_pgrp, i_session,
                i_tty_nr, i_tpgid, i_flags, i_minflt, i_cminflt, i_majflt, i_cmajflt,
                i_utime, i_stime, i_cutime, i_cstime, i_priority, i_nice,
                i_num_threads, i_itrealvalue, i_starttime, i_vsize, i_rss,
                i_exit_signal, i_processor, i_rt_priority, i_policy,
-               i_delayacct_blkio_ticks, i_uid, i_username};
+               i_delayacct_blkio_ticks, i_uid, i_username, i_rchar, i_wchar, i_syscr,
+               i_syscw, i_reads, i_writes, i_cwrites};
 
 int get_proctab(FuncCallContext *, char **);
 
@@ -129,7 +146,7 @@ Datum pg_proctab(PG_FUNCTION_ARGS)
 
                char **values = NULL;
 
-               values = (char **) palloc(32 * sizeof(char *));
+               values = (char **) palloc(39 * sizeof(char *));
                values[i_pid] = (char *) palloc((INTEGER_LEN + 1) * sizeof(char));
                values[i_comm] = (char *) palloc(1024 * sizeof(char));
                values[i_state] = (char *) palloc(2 * sizeof(char));
@@ -168,6 +185,13 @@ Datum pg_proctab(PG_FUNCTION_ARGS)
                values[i_delayacct_blkio_ticks] =
                                (char *) palloc((BIGINT_LEN + 1) * sizeof(char));
                values[i_uid] = (char *) palloc((INTEGER_LEN + 1) * sizeof(char));
+               values[i_rchar] = (char *) palloc((BIGINT_LEN + 1) * sizeof(char));
+               values[i_wchar] = (char *) palloc((BIGINT_LEN + 1) * sizeof(char));
+               values[i_syscr] = (char *) palloc((BIGINT_LEN + 1) * sizeof(char));
+               values[i_syscw] = (char *) palloc((BIGINT_LEN + 1) * sizeof(char));
+               values[i_reads] = (char *) palloc((BIGINT_LEN + 1) * sizeof(char));
+               values[i_writes] = (char *) palloc((BIGINT_LEN + 1) * sizeof(char));
+               values[i_cwrites] = (char *) palloc((BIGINT_LEN + 1) * sizeof(char));
 
                if (get_proctab(funcctx, values) == 0)
                        SRF_RETURN_DONE(funcctx);
@@ -412,6 +436,38 @@ get_proctab(FuncCallContext *funcctx, char **values)
                GET_NEXT_VALUE(p, q, values[i_delayacct_blkio_ticks], length,
                                "delayacct_blkio_ticks not found", ' ');
        }
+
+       /* Get i/o stats per process. */
+
+       sprintf(buffer, "%s/%d/io", PROCFS, pid);
+       fd = open(buffer, O_RDONLY);
+       if (fd == -1)
+       {
+               /* If the i/o stats are not available, set the values to zero. */
+               elog(NOTICE, "i/o stats collection for Linux not enabled");
+               strcpy(values[i_rchar], "0");
+               strcpy(values[i_wchar], "0");
+               strcpy(values[i_syscr], "0");
+               strcpy(values[i_syscw], "0");
+               strcpy(values[i_reads], "0");
+               strcpy(values[i_writes], "0");
+               strcpy(values[i_cwrites], "0");
+       }
+       else
+       {
+               len = read(fd, buffer, sizeof(buffer) - 1);
+               close(fd);
+               buffer[len] = '\0';
+               p = buffer;
+               GET_VALUE(values[i_rchar]);
+               GET_VALUE(values[i_wchar]);
+               GET_VALUE(values[i_syscr]);
+               GET_VALUE(values[i_syscw]);
+               GET_VALUE(values[i_reads]);
+               GET_VALUE(values[i_writes]);
+               GET_VALUE(values[i_cwrites]);
+       }
+
 #endif /* __linux__ */
 
        elog(DEBUG5, "pg_proctab: [%d] uid %s", (int) i_uid, values[i_uid]);
@@ -471,6 +527,20 @@ get_proctab(FuncCallContext *funcctx, char **values)
                        values[i_policy]);
        elog(DEBUG5, "pg_proctab: [%d] delayacct_blkio_ticks = %s",
                        (int) i_delayacct_blkio_ticks, values[i_delayacct_blkio_ticks]);
+       elog(DEBUG5, "pg_proctab: [%d] rchar = %s", (int) i_rchar,
+                       values[i_rchar]);
+       elog(DEBUG5, "pg_proctab: [%d] wchar = %s", (int) i_wchar,
+                       values[i_wchar]);
+       elog(DEBUG5, "pg_proctab: [%d] syscr = %s", (int) i_syscr,
+                       values[i_syscr]);
+       elog(DEBUG5, "pg_proctab: [%d] syscw = %s", (int) i_syscw,
+                       values[i_syscw]);
+       elog(DEBUG5, "pg_proctab: [%d] reads = %s", (int) i_reads,
+                       values[i_reads]);
+       elog(DEBUG5, "pg_proctab: [%d] writes = %s", (int) i_writes,
+                       values[i_writes]);
+       elog(DEBUG5, "pg_proctab: [%d] cwrites = %s", (int) i_cwrites,
+                       values[i_cwrites]);
 
        return 1;
 }

diff --git a/pg_proctab.sql.in b/pg_proctab.sql.in
index 8367e870d376a8d3ded2a2e18c96b2b408ac251b..c52987cb84c16c6773e05ddae1b8ca2f72e2a075 100644 (file)
--- a/pg_proctab.sql.in
+++ b/pg_proctab.sql.in
@@ -31,7 +31,14 @@ CREATE OR REPLACE FUNCTION pg_proctab(
                OUT policy BIGINT,
                OUT delayacct_blkio_ticks BIGINT,
                OUT uid INTEGER,
-               OUT username VARCHAR)
+               OUT username VARCHAR,
+               OUT rchar BIGINT,
+               OUT wchar BIGINT,
+               OUT syscr BIGINT,
+               OUT syscw BIGINT,
+               OUT reads BIGINT,
+               OUT writes BIGINT,
+               OUT cwrites BIGINT)
 RETURNS SETOF record
 AS 'MODULE_PATHNAME', 'pg_proctab'
 LANGUAGE C IMMUTABLE STRICT;