View Statistics and Metrics

This content covers the statistics and metrics collected and made available by Sync Gateway
Sync Gateway’s statistics and metrics provide under-the-hood data on the performance, resource utilization and health of it nodes. This is increasingly important as deployments scale to support a large numbers of connected mobile and edge components.

Related inter-syncgateway topics: Legacy Pre-3.0 Configuration | Metrics REST API | Prometheus Integration

Introduction

Deployments are increasingly scaling to support large numbers of connected mobile and edge clients. This places added emphasis on the effective monitoring of the health and performance of Sync Gateway nodes.

Sync Gateway’s Metrics REST API_ facilitates the process of gathering this essential data by providing access to node metrics covering:

Performance
Resource utilization
Health

It also provides for integration with Prometheus.

Access the Data

Use the Metrics REST API to request the statistics in either JSON format or Prometheus format.

JSON format

Use the _expvars method to request these metrics, as shown in Example 1:

Example 1. Metrics in JSON format

curl -X GET "http://localhost:4986/_expvar" -H "accept: application/json"

The response is a JSON object with the schema detailed in Sync Gateway Stats Schema, use the click-through links to find out more about each item.

Prometheus format

Use the _metrics method to request these metrics, as shown in Example 2:

Example 2. Metrics in Prometheus format

curl -X GET "http://localhost:4986/_metrics" -H "accept: application/json"

The response, in Prometheus format, comprises the data detailed in Sync Gateway Stats Schema.

This endpoint’s data will be scraped at configurable interval, when the metricsInterface is activated and Sync Gateway integrated with Prometheus — see: Prometheus Integration and our blog entry Monitoring Couchbase Sync Gateway with Prometheus and Grafana.

Sync Gateway Stats Schema

The statistics detailed in this schema are reset at each node restart; that is they are not persisted. So all totals, counts and averages are the values accrued since the last node restart unless otherwise specified.

"syncgateway": {
  "global": {
    "resource_utilization": {
      "admin_net_bytes_recv": 0,
      "admin_net_bytes_sent": 0,
      "error_count": 0,
      "go_memstats_heapalloc": 0,
      "go_memstats_heapidle": 0,
      "go_memstats_heapinuse": 0,
      "go_memstats_heapreleased": 0,
      "go_memstats_pausetotalns": 0,
      "go_memstats_stackinuse": 0,
      "go_memstats_stacksys": 0,
      "go_memstats_sys": 0,
      "goroutines_high_watermark": 0,
      "num_goroutines": 0,
      "process_memory_resident": 0,
      "pub_net_bytes_recv": 0,
      "pub_net_bytes_sent": 0,
      "system_memory_total": 0,
      "warn_count": 0,
      "process_cpu_percent_utilization": 0,
      "uptime": 0
    }
  },
  "per_db":  {
    [
      "$dbname": {
        "cache": {
          "abandoned_seqs":0,
          "chan_cache_active_revs": 0,
          "chan_cache_bypass_count": 0,
          "chan_cache_channels_added": 0,
          "chan_cache_channels_evicted_inactive": 0,
          "chan_cache_channels_evicted_nru": 0,
          "chan_cache_compact_count": 0,
          "chan_cache_compact_time": 0,
          "chan_cache_hits": 0,
          "chan_cache_max_entries": 0,
          "chan_cache_misses": 0,
          "chan_cache_num_channels": 0,
          "chan_cache_pending_queries":0,
          "chan_cache_removal_revs": 0,
          "chan_cache_tombstone_revs": 0,
          "high_seq_cached": 0,
          "high_seq_stable": 0,
          "num_active_channels": 0,
          "pending_seq_len": 0,
          "num_skipped_seqs": 0,
          "rev_cache_bypass": 0,
          "rev_cache_hits": 0,
          "rev_cache_misses": 0,
          "skipped_seq_len": 0,
          "view_queries": 0
        },
        "cbl_replication_pull": {
          "attachment_pull_bytes": 0,
          "attachment_pull_count": 0,
          "max_pending": 0,
          "num_pull_repl_active_continuous": 0,
          "num_pull_repl_active_one_shot": 0,
          "num_pull_repl_caught_up": 0,
          "num_pull_repl_since_zero": 0,
          "num_pull_repl_total_continuous": 0,
          "num_pull_repl_total_one_shot": 0,
          "request_changes_count": 0,
          "request_changes_time": 0,
          "rev_processing_time": 0,
          "rev_send_count": 0,
          "rev_send_latency": 0
        },
        "cbl_replication_push": {
          "attachment_push_bytes": 0,
          "attachment_push_count": 0,
          "conflict_write_count": 0,
          "doc_push_count": 0,
          "propose_change_count": 0,
          "propose_change_time": 0,
          "sync_function_count": 0,
          "sync_function_time": 0,
          "write_processing_time": 0
        },
        "database": {
          "compaction_attachment_start_time": 0,
          "compaction_tombstone_start_time": 0,
          "crc32c_match_count": 0,
          "dcp_caching_count": 0,
          "dcp_caching_time": 0,
          "dcp_received_count": 0,
          "dcp_received_time": 0,
          "doc_reads_bytes_blip": 0,
          "doc_writes_bytes": 0,
          "doc_writes_xattr_bytes":0,
          "high_seq_feed":0,
          "num_attachments_compacted": 0,
          "doc_writes_bytes_blip": 0,
          "num_doc_reads_blip": 0,
          "num_doc_reads_rest": 0,
          "num_doc_writes": 0,
          "num_replications_active": 0,
          "num_replications_total": 0,
          "sequence_assigned_count": 0,
          "sequence_get_count": 0,
          "sequence_incr_count":0,
          "sequence_released_count": 0,
          "sequence_reserved_count": 0,
          "warn_channel_name_size_count": 0,
          "warn_channels_per_doc_count": 0,
          "warn_grants_per_doc_count": 0,
          "warn_xattr_size_count": 0,
          "sync_function_count": 0,
          "sync_function_time": 0,
          "import_feed": 0
        },
        "delta_sync": {
          "delta_cache_hit": 0,
          "delta_cache_miss": 0,
          "delta_pull_replication_count": 0,
          "delta_push_docs_count": 0,
          "deltas_requested": 0,
          "deltas_sent": 0
        },
        "gsi_views": {
          "GSIs": 0,
            "{query name}_count": 0,
            "{query name}_error_count": 0,
            "{query name}_time": 0,
          "Views (Design doc or view)": 0,
            "{design doc name}.{view name}_count": 0,
            "{design doc name}.{view name}_error_count": 0,
            "{design doc name}.{view name}_time": 0,
        },
        "security": {
          "auth_failed_count": 0,
          "auth_success_count": 0,
          "num_access_errors": 0,
          "num_docs_rejected": 0,
          "total_auth_time": 0
        },
        "shared_bucket_import": {
          "import_cancel_cas": 0,
          "import_count": 0,
          "import_error_count": 0,
          "import_high_seq": 0,
          "import_partitions": 0,
          "import_processing_time": 0
        },
        "per_replication": {
          [
            "$replname": {
              "sgr_num_docs_pushed": 0,
              "sgr_num_docs_failed_to_push": 0,
              "sgr_docs_checked_sent": 0,
              "sgr_num_attachments_pushed": 0,
              "sgr_num_attachment_bytes_pushed": 0,
              "sgr_num_attachments_pulled": 0,
              "sgr_num_attachment_bytes_pulled": 0,
              "sgr_num_docs_pulled": 0,
              "sgr_num_docs_purged": 0,
              "sgr_num_docs_failed_to_pull": 0,
              "sgr_push_conflict_count": 0,
              "sgr_push_rejected_count": 0,
              "sgr_docs_checked_recv": 0,
              "sgr_deltas_recv": 0,
              "sgr_deltas_requested": 0,
              "sgr_deltas_sent": 0,
              "sgr_conflict_resolved_local_count": 0,
              "sgr_conflict_resolved_remote_count": 0,
              "sgr_conflict_resolved_merge_count": 0
              }
          ]
        }
    ]
  },
  "per_replication": {
    "$replname": {
      "sgr_active": true,
      "sgr_num_attachments_transferred": 0,
      "sgr_num_attachment_bytes_transferred": 0,
      "sgr_num_docs_pushed": 0,
      "sgr_num_docs_failed_to_push": 0,
      "sgr_docs_checked_sent": 0
    }
  }
}

Global stats

syncgateway

Monitoring stats for Sync Gateway.

global

Global Sync Gateway stats.

resource_utilization

Resource utilization stats,

See: https://golang.org/pkg/runtime/#MemStats for more on memory allocator statistics.

admin_net_bytes_recv

Description: The total number of bytes received (since node start-up) on the network interface to which the Sync Gateway api.admin_interface is bound.

By default, that is the number of bytes received on 127.0.0.1:4985 since node start-up.
Use Case: This metric can be used to determine throughput on the admin interface:

throughput = admin_net_bytes_recv / admin_net_bytes_sent

admin_net_bytes_sent

Description: The total number of bytes sent (since node start-up) on the network interface to which the Sync Gateway api.admin_interface is bound.

By default, that is the number of bytes sent on 127.0.0.1:4985 since node start-up.
Use Case: This metric can be useful in calculating the throughput on Sync Gateway’s admin interface:

throughput = admin_net_bytes_recv / admin_net_bytes_sent

error_count

The total number of errors logged.

memory allocator statistics

See: https://golang.org/pkg/runtime/#MemStats for more on memory allocator statistics.

go_memstats_heapalloc

Go memstats.HeapAlloc — Go memstats

go_memstats_heapidle

Go memstats.HeapIdle — Go memstats

go_memstats_heapinuse

Go memstats.HeapInuse — Go memstats

go_memstats_heapreleased

Go memstats.HeapReleased — Go memstats

go_memstats_pausetotalns

Go memstats.PauseTotalNs — Go memstats

go_memstats_stackinuse

Go memstats.StackInuse — Go memstats

go_memstats_stacksys

Go memstats.StackSys — Go memstats

go_memstats_sys

Go memstats.Sys — Go memstats

goroutines_high_watermark

Peak number of go routines since process start.

num_goroutines

The total number of goroutines.

process_cpu_percent_utilization

Description: The CPU’s utilization as percentage value.
Derivation: The CPU usage calculation is performed based on user and system CPU time, but it doesn’t include components such as iowait.
Constraints: The derivation means that the values of process_cpu_percent_utilization and %Cpu, returned when running the top command, will differ.

process_memory_resident

The memory utilization (Resident Set Size) for the process, in bytes.

pub_net_bytes_recv

Description: The total number of bytes received (since node start-up) on the network interface to which the Sync Gateway api.public_interface is bound.

By default, that is the number of bytes received on 127.0.0.1:4984 since node start-up.
Use Case: The metric can be used to calculate throughput on the public interface:

throughput = pub_net_bytes_recv / pub_net_bytes_sent

pub_net_bytes_sent

Description: The total number of bytes sent (since node start-up) on the network interface to which Sync Gateway api.public_interface is bound.

By default, that is the number of bytes sent on 127.0.0.1:4984 since node start-up.
Use Case: This metric can be used to calculate throughput on the public interface:

throughput = pub_net_bytes_recv / pub_net_bytes_sent

system_memory_total

Description: The total memory available on the system in bytes.

warn_count

Description: The total number of warnings logged.

uptime

Description: The total uptime.

Metrics by Database

Quick Links

per_db

The metrics for each database declared in the config file.

$dbname

The metrics relating to a database declared in the config file.

cache

These metrics relate to caching.

abandoned_seqs

Description: The total number of skipped sequences that were not found after 60 minutes and were abandoned.

chan_cache_active_revs

Description: The total number of active revisions in the channel cache.

chan_cache_bypass_count

Description: The total number of transient bypass channel caches created to serve requests when the channel cache was at capacity.

chan_cache_channels_added

Description: The total number of channel caches added.
Constraints: The metric doesn’t decrease when a channel is removed. That is, it is similar to chan_cache_num_channels but doesn’t track removals.

chan_cache_channels_evicted_inactive

Description: The total number of channel cache channels evicted due to inactivity.

chan_cache_channels_evicted_nru

Description: The total number of active channel cache channels evicted, based on ‘not recently used’ criteria.

chan_cache_compact_count

Description: The total number of channel cache compaction runs.

chan_cache_compact_time

Description: The total amount of time taken by channel cache compaction across all compaction runs.

chan_cache_hits

Description: The total number of channel cache requests fully served by the cache.
Use Case: This metric is useful in calculating the channel cache hit ratio:

channel cache hit ratio = chan_cache_hits / (chan_cache_hits + chan_cache_misses)

chan_cache_max_entries

Description: The total size of the largest channel cache.
Use Case: This metric helps with channel cache tuning, and provides a hint on cache size variation (when compared to average cache size).

chan_cache_misses

Description: The total number of channel cache requests not fully served by the cache.
Use Case: This metric is useful when calculating the channel cache hit ratio:

channel cache hit ratio = chan_cache_hits / (chan_cache_hits + chan_cache_misses)

chan_cache_num_channels

Description: The total number of channels being cached.
Use Case: The total number of channels being cached provides insight into potential max cache size requirements and also node usage (for example, chan_cache_num_channels * max_cache_size).

chan_cache_pending_queries

Description: The total number of channel cache pending queries.

chan_cache_removal_revs

Description: The total number of removal revisions in the channel cache.
Use Case: This metric acts as a reminder that removals must be considered when tuning the channel cache size and also helps users understand whether they should be tuning tombstone retention policy (metadata purge interval) and running compact.

chan_cache_tombstone_revs

Description: The total number of tombstone revisions in the channel cache.
Use Case: This metric acts as a reminder that tombstones and removals must be considered when tuning the channel cache size and also helps users understand whether they should be tuning tombstone retention policy (metadata purge interval), and running compact.

high_seq_cached

Description: The highest sequence number cached.
Constraints: There may be skipped sequences lower than high_seq_cached.

high_seq_stable

Description: The highest contiguous sequence number that has been cached.

num_active_channels

Description: The total number of active channels.

num_skipped_seqs

Description: The total number of skipped sequences.
Use Case: This metric helps with channel cache tuning, and provides a hint on cache size variation (when compared to average cache size).

pending_seq_len

Description: The total number of pending sequences. These are out-of-sequence entries waiting to be cached.

rev_cache_bypass

Description: The total number of revision cache bypass operations performed.

rev_cache_hits

Description: The total number of revision cache hits.
Use Case: This metric can be used to calculate the ratio of revision cache hits:

Rev Cache Hit Ratio = rev_cache_hits / (rev_cache_hits + rev_cache_misses)

rev_cache_misses

Description: The total number of revision cache misses.
Use Case: This metric can be used to calculate the ratio of revision cache misses:

Rev Cache Miss Ratio = rev_cache_misses / (rev_cache_hits + rev_cache_misses)

skipped_seq_len

Description: The current length of the pending skipped sequence queue.

view_queries

Description: The total view_queries.

cbl_replication_pull

attachment_pull_bytes

Description: The total size of attachments pulled. This is the pre-compressed size.

attachment_pull_count

Description: The total number of attachments pulled.

max_pending

Description: The high watermark for the number of documents buffered during feed processing, waiting on a missing earlier sequence.

num_pull_repl_active_continuous

Description: The total number of continuous pull replications in the active state.

num_pull_repl_active_one_shot

Description: The total number of one-shot pull replications in the active state.

num_pull_repl_caught_up

Description: The total number of replications which have caught up to the latest changes.

num_pull_repl_since_zero

Description: The total number of new replications started (/_changes?since=0).

num_pull_repl_total_continuous

Description: The total number of continuous pull replications.

num_pull_repl_total_one_shot

Description: The total number of one-shot pull replications.

request_changes_count

Description: The total number of changes requested.
Use Case: This metric can be used to calculate the latency of requested changes:

changes request latency = request_changes_time / request_changes_count

request_changes_time

Description
Use Case: This metric can be used to calculate the latency of requested changes:

changes request latency = request_changes_time / request_changes_count

rev_processing_time

Description: The total amount of time processing rev messages (revisions) during pull revision.
Use Case: This metric can be used with rev_send_count to calculate the average processing time per revision:

average processing time per revision = rev_processing_time / rev_send_count

rev_send_count

Description: The total number of rev messages processed during replication.
Use Case: This metric can be used with rev_processing_time to calculate the average processing time per revision:

average processing time per revision = rev_processing_time / rev_send_count.

rev_send_latency

Description: The total amount of time between Sync Gateway receiving a request for a revision and that revision being sent.

In a pull replication, Sync Gateway sends a /_changes request to the client and the client responds with the list of revisions it wants to receive.

So, rev_send_latency measures the time between the client asking for those revisions and Sync Gateway sending them to the client.
Use Case: This metric gives the time taken to respond to a / changes request.
Constraints

The derived value includes latency associated with processing other revisions in the same batch.

Measuring time from the /_changes response means that this stat will vary significantly depending on the changes batch size A larger batch size will result in a spike of this stat, even if the processing time per revision is unchanged.

A more useful stat might be the average processing time per revision:

average processing time per revision = rev_processing_time] / rev_send_count

cbl_replication_push

attachment_push_bytes

Description: The total number of attachment bytes pushed.

compaction_attachment_start_time

Description: The compaction_attachment_start_time.

compaction_tombstone_start_time

Description: The compaction_tombstone_start_time.

attachment_push_count

Description: The total number of attachments pushed.

conflict_write_count

Description: The total number of writes that left the document in a conflicted state. Includes new conflicts, and mutations that don’t resolve existing conflicts.

doc_push_count

Description: The total number of documents pushed.

propose_change_count

Description

The total number of changes and-or proposeChanges messages processed since node start-up.

Use Case

The propose_change_count stat can be useful when:

Assessing the number of redundant requested changes being pushed by the client.

Do this by comparing the propose_change_count value with the number of actual writes num_doc_writes, which could indicate that clients are pushing changes already known to Sync Gateway.
Identifying situations where push replications are unexpectedly being restarted from zero.

P2P synchronizations will typically show a higher incidences of rejected proposed changes.

propose_change_time

Description: The total time spent processing changes and/or proposeChanges messages.
Use Case: The propose_change_time stat can be useful in diagnosing push replication issues arising from potential bottlenecks changes and-or proposeChanges processing.
Contraints: The propose_change_time is not included in the write_processing_time.

sync_function_count

Description: The total number of times that the sync_function is evaluated.
Use Case: The {sync_function_count_ stat is useful in assessing the usage of the sync_function, when used in conjunction with the sync_function_time.

sync_function_time

Description

The total time spent evaluating the sync_function.

Use Case

The sync_function_time stat can be useful when:

Troubleshooting excessively long push times, where it can help identify potential sync_function bottlenecks (for example, those arising from complex, or inefficient, sync_function design
Assessing the overall contribution of the sync_function processing to overall push replication write times.

write_processing_time

Description

Total time spent processing writes. Measures complete request-to-response time for a write.

Use Case

The write_processing_time stat can be useful when:

Determining the average time per write:

average time per write = write_processing_time / num_doc_writes stat value
Assessing the benefit of adding additional Sync Gateway nodes, as it can point to Sync Gateway being a bottleneck
Troubleshooting slow push replication, in which case it ought to be considered in conjunction with sync_function_time.

database

Stats relative to the database

abandoned_seqs

Description: The total number of skipped sequences abandoned, based on cache.channel_cache.max_wait_skipped.

cache_feed

Description

Contains low level dcp stats:

dcp_backfill_expected - the expected number of sequences in backfill
dcp_backfill_completed - the number of backfill items processed
dcp_rollback_count - the number of DCP rollbacks.

crc32c_match_count

Description: The total number of instances during import when the document cas had changed, but the document was not imported because the document body had not changed.

dcp_caching_count

Description: The total number of DCP mutations added to Sync Gateway’s channel cache.
Use Case: Can be used with dcp_caching_time to monitor cache processing latency. That is, the time between seeing a change on the DCP feed and when it’s available in the channel cache:

DCP cache latency = dcp_caching_time / dcp_caching_count

dcp_caching_time

Description: The total time between a DCP mutation arriving at Sync Gateway and being added to channel cache.
Use Case: This metric can be used with dcp_caching_count to monitor cache processing latency. That is, the time between seeing a change on the DCP feed and when it’s available in the channel cache:

dcp_cache_latency = dcp_caching_time / dcp_caching_count

dcp_received_count

Description: The total number of document mutations received by Sync Gateway over DCP.

dcp_received_time

Description: The time between a document write and that document being received by Sync Gateway over DCP. If the document was written prior to Sync Gateway starting the feed, it is recorded as the time since the feed was started.
Use Case: This metric can be used to monitor DCP feed processing latency.

doc_reads_bytes_blip

Description: The total number of bytes read via Couchbase Lite 2.x replication since Sync Gateway node startup.

doc_writes_bytes

Description: The total number of bytes written as part of document writes since Sync Gateway node startup.

doc_writes_bytes_blip

Description: The total number of bytes written as part of Couchbase Lite document writes since Sync Gateway node startup.

doc_writes_xattr_bytes

Description: The total size of xattrs written (in bytes).

high_seq_feed

Description: Highest sequence number seen on the caching DCP feed.

num_attachments_compacted

Description: The number of attachments compacted

import_feed

Description

This metric contains low level dcp stats:

dcp_backfill_expected - the total expected number of sequences in backfill
dcp_backfill_completed - the total number of backfill items processed
dcp_rollback_count - the total number of rollbacks that occur.

num_doc_reads_blip

Description: The total number of documents read via Couchbase Lite 2.x replication since Sync Gateway node startup.

num_doc_reads_rest

Description: The total number of documents read via the REST API since Sync Gateway node startup. Includes Couchbase Lite 1.x replication.

num_doc_writes

Description: The total number of documents written by any means (replication, rest API interaction or imports) since Sync Gateway node startup.

num_replications_active

Description: The total number of active replications.
Constraints: This metric only counts continuous pull replications.

num_replications_total

Description: The total number of replications created since Sync Gateway node startup.

sequence_assigned_count

Description: The total number of sequence numbers assigned.

sequence_get_count

Description: The total number of high sequence lookups.

sequence_incr_count

Description: The total number of times the sequence counter document has been incremented.

sequence_released_count

Description: The total number of unused, reserved sequences released by Sync Gateway.

sequence_reserved_count

Description: The total number of sequences reserved by Sync Gateway.

warn_channel_name_size_count

Description: The total number of warnings relating to the channel name size.

warn_channels_per_doc_count

Description: The total number of warnings relating to the channel count exceeding the channel count threshold.
Corresponding warning message

Doc id: {document id} channel count: {channel count} exceeds {channel count} for channels per doc warning threshold

warn_grants_per_doc_count

Description: The total number of warnings relating to the grant count exceeding the grant count threshold.
Corresponding warning message

Doc id: {document id} access and role grants count: {grant count} exceeds {grant count} for grants per doc warning threshold

warn_xattr_size_count

Description: The total number of warnings relating to the xattr sync data being larger than a configured threshold.
Corresponding warning message

Doc id: {document id} sync metadata size: {xattr bytes} bytes exceeds {xattr bytes} bytes for sync metadata warning threshold

delta_sync

delta_cache_hit

Description: The total number of requested deltas that were available in the revision cache.

delta_cache_miss

Description: The total number of requested deltas that were not available in the revision cache.

delta_pull_replication_count

Description: The number of delta replications that have been run.

delta_push_doc_count

Description: The total number of documents pushed as a delta from a previous revision.

deltas_requested

Description: The total number of times a revision is sent as delta from a previous revision.

deltas_sent

Description: The total number of revisions sent to clients as deltas.

gsi_views

GSIs

The GSI metrics are defined in this section, where {query name} is a placeholder representing a Valid Query Name from this list:

Valid Query Names

access
roleAccess
channels
channelsStar
sequences
principals
sessions
tombstones
resync
allDocs

{query name}_count

Description: The total number of queries performed.

{query name}_error_count

Description: The total number of errors that occurred when performing the query.

{query name}_time

Description: The total time taken to perform queries.

Views

The View metrics are defined in this section, where {design doc name} and {view name} are placeholders representing a Valid Design Doc Name and a Valid View Name, as defined in these lists:

Valid Design Doc Names

sync_gateway
sync_housekeeping

Valid View Names

principals
channels
access
access_vbseq
role_access
role_access_vbseq
all_docs
import
sessions
tombstones

{design doc name}.{view name}_count

Description: The total number of view queries performed.

{design doc name}.{view name}_error_count

Description: The total number of errors that occurred when performing the query.

{design doc name}.{view name}_time

Description: The total time taken to perform the view query.

Security

These metrics relate to security.

auth_failed_count

Description: The total number of unsuccessful authentications.
Use Case: This metric is useful in monitoring the number of authentication errors.

auth_success_count

Description: The total number of successful authentications.
Use Case: This metric is useful in monitoring the number of authenticated requests.

num_access_errors

Description: The total number of documents rejected by write access functions (requireAccess, requireRole, requireUser).

num_docs_rejected

Description: The total number of documents rejected by the sync_function.
Use Case: This metric is useful in debugging sync_function issues and identify unexpected incoming documents.

total_auth_time

Description: The total time spent in authenticating all requests.
Use Cases: This metric can be compared with auth_success_count and auth_failed_count to derive an average success and-or fail rate.

shared_bucket_import

import_cancel_cas

Description: The total number of imports cancelled due to cas failure.

import_count

Description: The total number of docs imported.

import_error_count

Description: The total number of errors arising as a result of a document import.
Corresponding Error Message

Error importing doc {document id}: {error}

import_high_seq

Description: The highest sequence number value imported.

import_partitions

Description: The total number of import partitions.

import_processing_time

Description: The total time taken to process a document import.

Metrics by replication

The metrics collated and reported here relate only to replications run using the inter-Sync Gateway replication.

These metrics refer to Sync Gateway replications only; Couchbase Lite replications are not included.

Per_replication

(Inter-Sync Gateway)

This per_replication group header encompasses all the stats for each inter-Sync Gateway replication involving its owning database.

It comprises an array of one or more $replname objects, each of which represents the statistics collected and recorded against the specified $replname (replication_id).

$replname

This object comprises the stats collected and recorded for the inter-Sync Gateway replication named $replname (which equates to a replication_id). The same structure is used to return statistics from Inter-Sync Gateway and SG Replicate replications, but not all items are populated by each version.

sgr_docs_checked_sent

Description

The total number of documents checked for changes since replication started. This represents the number of potential change notifications pushed by Sync Gateway.

Constraints

This is not necessarily the number of documents pushed, as a given target might already have the change.
Used by Inter-Sync Gateway and SG Replicate

Values

Continuous replication:

The value is true for the duration of the replication, and also once it has caught up (i.e is in the idle state). The value is false if the replication is explicitly cancelled.
One-shot replication

The value is true for the duration of the replication, and then false when it has completed or if it is cancelled.

Use Case

This metric can be useful when analyzing replication history, and to filter by active replications.

sgr_num_docs_failed_to_push

Description: The total number of documents that failed to be pushed since replication started.

Used by Inter-Sync Gateway and SG Replicate

sgr_num_docs_pushed

Description: The total number of documents that were pushed since replication started.

Used by Inter-Sync Gateway and SG Replicate

sgr_num_attachments_pushed

Description: The total number of attachments that were pushed since replication started.

sgr_num_attachment_bytes_pushed

Description: The total number of bytes in all the attachments that were pushed since replication started.

sgr_num_attachments_pulled

Description: The total number of attachments that were pulled since replication started.

sgr_num_attachment_bytes_pulled

Description: The total number of bytes in all the attachments that were pulled since replication started.

sgr_num_docs_pulled

Description: The total number of documents that were pulled since replication started.

sgr_num_docs_purged

Description: The total number of documents that were purged since replication started.

sgr_num_docs_failed_to_pull

Description: The total number of document pulls that failed since replication started.

sgr_push_conflict_count

Description: The total number of pushed documents that conflicted since replication started.

sgr_push_rejected_count

Description: The total number of pushed documents that were rejected since replication started.

sgr_docs_checked_recv

Description: The total number of documents that were purged since replication started.

sgr_deltas_recv

Description: The total number of documents that were purged since replication started.

sgr_deltas_requested

Description: The total number of deltas requested

sgr_deltas_sent

Description: The total number of deltas sent

sgr_conflict_resolved_local_count

Description: The total number of conflicting documents that were resolved successfully locally (by the active replicator)

sgr_conflict_resolved_remote_count

Description: The total number of conflicting documents that were resolved successfully remotely (by the active replicator)

sgr_conflict_resolved_merge_count

Description: The total number of conflicting documents that were resolved successfully by a merge action (by the active replicator)

sgw_conflict_skipped_error

Description: The total number of documents that were skipped during sync because of an error in conflict resolution

Metrics by replication ( *deprecated )

This structure and its associated metrics is deprecated at version 2.8. The metrics collated and reported here relate only to replications run using the SG Replicate. For metrics relating to replications run using inter-Sync Gateway replication see: Per_replication.

Per_replication (SG Replicate)

This per_replication group header encompasses all the stats for each inter-Sync Gateway replication involving its owning database.

It comprises an array of one or more $replname objects, each of which represents the statistics collected and recorded against the specified $replname (replication_id).

These metrics refer to Sync Gateway replications only; Couchbase Lite replications are not included.