# Monitoring

> Source chapter 3.6 for PostgreSQL 10.

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LLMS index: [llms.txt](/en/llms.txt)

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<div class="feature-source-note"><span class="feature-edition-badge">Beta 1</span><span><strong>Source pages:</strong> PDF 58-59</span><span><a href="https://github.com/nori-shinoda/documents/blob/1773200c5362476c4a549222b7d17fa91f546cae/postgresql10_beta1_new_features_en_20170522-1.pdf">Original PDF on GitHub</a></span></div>

<p class="feature-page-marker" id="pgfeat-10-monitoring-pdf-page-58">PDF page 58</p>

#### 3.6.1 Monitor wait events {#pg10-3-6-1-monitor-wait-events}

Wait events that are shown in the wait_event_type and wait_event columns of the pg_stat_activity catalog have been added. LWLockNamed and LWLockTranche that were output in the wait_event_type column in PostgreSQL 9.6 have been renamed to LWLock.

**Table 23.** Value to be output to the wait\_event\_type column

| wait_event_type | Description | Change |
| --- | --- | --- |
| column |  |  |
| LWLockLockBufferPin | Light weight lock wait Lock wait Waiting for buffer | Renamed |
| Activity | Waiting for processing acceptance of background processes | Added |
| Client | A state in which the client is waiting for processing | Added |
| Extension | Wait for background worker | Added |
| IPC | A state waiting for processing from another process | Added |
| Timeout | Waiting for timeout | Added |
| IO | Waiting for I / O | Added |

#### 3.6.2 EXPLAIN SUMMARY statement {#pg10-3-6-2-explain-summary-statement}

A SUMMARY clause has been added to the EXPLAIN statement to output only the execution plan generation time.

**Example 60.** EXPLAIN SUMMARY

```text
postgres=> EXPLAIN (SUMMARY) SELECT * FROM data1 ;
                           QUERY PLAN
----------------------------------------------------------------
 Seq Scan on data1  (cost=0.00..15406.00 rows=1000000 width=11)
 Planning time: 0.072 ms
(2 rows)
```

#### 3.6.3 VACUUM VERBOSE statement {#pg10-3-6-3-vacuum-verbose-statement}

Oldest xmin and frozen pages are now output as the output of the VACUUM VERBOSE statement.

<p class="feature-page-marker" id="pgfeat-10-monitoring-pdf-page-59">PDF page 59</p>

**Example 61.** Execute VACUUM VERBOSE statement

```text
postgres=> VACUUM VERBOSE data1 ;
NFO:  vacuuming "public.data1"
…
DETAIL:  0 dead row versions cannot be removed yet, oldest xmin: 587
There were 0 unused item pointers.
Skipped 0 pages due to buffer pins, 0 frozen pages.
0 pages are entirely empty.
…
```