Add info text for wal and update for checkpoints (#13607)

1 files changed, 5 insertions, 2 deletions

diff --git a/web/gui/dashboard_info.js b/web/gui/dashboard_info.js
index b84a762075..ac56f47685 100644
--- a/web/gui/dashboard_info.js
+++ b/web/gui/dashboard_info.js
@@ -3825,10 +3825,10 @@ netdataDashboard.context = {
         info: '<p><b>Connections usage</b> across all databases. The maximum number of concurrent connections to the database server is (<i>max_connections</i> - <i>superuser_reserved_connections</i>). As a general rule, if you need more than 200 connections it is advisable to use connection pooling.</p><p><b>Available</b> - new connections allowed. <b>Used</b> - connections currently in use.</p>'
     },
     'postgres.checkpoints': {
-        info: '<p>Number of checkpoints that have been performed. Checkpoints are periodic maintenance operations the database performs to make sure that everything it’s been caching in memory has been synchronized with the disk. It’s desirable when checkpoints are scheduled rather than requested, as the latter can indicate that your databases are under heavy load.</p><p><b>Scheduled</b> - checkpoints triggered due that the time elapsed from the previous checkpoint is more than pg setting <i>checkpoint_timeout</i>. <b>Requested</b> - checkpoints ran due to uncheckpointed WAL size grew to more than <i>max_wal_size</i> setting.</p>'
+        info: '<p>Number of checkpoints that have been performed. Checkpoints are periodic maintenance operations the database performs to make sure that everything it’s been caching in memory has been synchronized with the disk. Ideally checkpoints should be time-driven (scheduled) as opposed to load-driven (requested).</p><p><b>Scheduled</b> - checkpoints triggered as per schedule when time elapsed from the previous checkpoint is greater than <a href="https://www.postgresql.org/docs/current/runtime-config-wal.html#GUC-CHECKPOINT-TIMEOUT" target="_blank"><i>checkpoint_timeout</i></a>. <b>Requested</b> - checkpoints triggered due to WAL updates reaching the <a href="https://www.postgresql.org/docs/current/runtime-config-wal.html#GUC-MAX-WAL-SIZE" target="_blank"><i>max_wal_size</i></a> before the <i>checkpoint_timeout</i> is reached.</p>'
     },
     'postgres.checkpoint_time': {
-        info: '<p>Checkpoint timing information.</p><p><b>Write</b> - amount of time that has been spent in the portion of checkpoint processing where files are written to disk. <b>Sync</b> - amount of time that has been spent in the portion of checkpoint processing where files are synchronized to disk.</p>'
+        info: '<p>Checkpoint timing information. An important indicator of how well checkpoint I/O is performing is the amount of time taken to sync files to disk.</p><p><b>Write</b> - amount of time spent writing files to disk during checkpoint processing. <b>Sync</b> - amount of time spent synchronizing files to disk during checkpoint processing.</p>'
     },
     'postgres.bgwriter_buffers_alloc': {
         info: 'Allocated and re-allocated buffers. If a backend process requests data it is either found in a block in shared buffer cache or the block has to be allocated (read from disk). The latter is counted as <b>Allocated</b>.'
@@ -3842,6 +3842,9 @@ netdataDashboard.context = {
     'postgres.bgwriter_buffers_backend_fsync': {
         info: 'Number of times a backend had to execute its own fsync call (normally the background writer handles those even when the backend does its own write). Any values above zero can indicate problems with storage when fsync queue is completely filled. '
     },
+    'postgres.wal_writes': {
+        info: 'Write-Ahead Logging (WAL) ensures data integrity by ensuring that changes to data files (where tables and indexes reside) are written only after log records describing the changes have been flushed to permanent storage.'
+    },
     'postgres.wal_archive_files': {
         info: '<p>WAL archiving.</p><p><b>Ready</b> - WAL files waiting to be archived. A non-zero value can indicate <i>archive_command</i> is in error, see <a href="https://www.postgresql.org/docs/current/static/continuous-archiving.html" target="_blank">Continuous Archiving and Point-in-Time Recovery</a> <b>Done</b> - WAL files successfully archived.'
     },