# syslog_ident

> syslog_ident is the PostgreSQL setting that defines the program name used to identify PostgreSQL messages in syslog.
---

> [!NOTE]
> **Fact — official short description:** “Sets the program name used to identify PostgreSQL messages in syslog.”

## Identity {#identity}

| Field | Value | Meaning |
| --- | --- | --- |
| Type | `string` | Upstream pg_settings type |
| Context | `sighup` | Takes effect after configuration reload |
| Unit | — | Raw unit |
| Range | — | Raw limits in the last observed version |
| Enum values | — | — for non-enum types |
| Category | Reporting and Logging / Where to Log | Upstream classification |
| Latest boot value | `postgres` | postgres |
{.fields meta="-"}

## Lifecycle {#lifecycle}

| Fact | Value |
| --- | --- |
| First observed | PG9.0 (research boundary) |
| Present in | PG9.0–19 Beta 3 |
| Removed in | No |
| Introduction commit | Not asserted: predates the PG9.0 research boundary |
| Commit date | — |
| Discussion | — |

## Default history {#default-history}

| Versions | Raw `boot_val` | Unit | Human value |
| --- | --- | --- | --- |
| PG9.0–19 Beta 3 | `postgres` | — | postgres |
{.full-width caption="Measured PG9.0–19 Beta 3 boot defaults"}

## How it works {#mechanism}

syslog_ident sets the program name used to identify PostgreSQL messages in syslog. The ident labels PostgreSQL records in syslog and can distinguish clusters when combined with facility or host metadata.

syslog_ident is a SIGHUP-context setting: a configuration reload activates the new server value without a restart; subsequent operations that consult it use the refreshed value.

It is active only when syslog appears in log_destination, after which the facility, ident, sequence, splitting, host daemon, and remote receiver jointly define record delivery.

## Tuning advice {#tuning-advice}

> [!TIP]
> **Advice.** These are workload-specific starting points and must be validated with measurements.

| Workload | Guidance |
| --- | --- |
| OLTP | Set syslog_ident to match the receiving syslog daemon's routing, framing, deduplication, and message-size contract; validate failover and backpressure with the real collector. |
| OLAP | Test syslog_ident under bursty analytical messages and multiline plans so splitting or receiver limits do not destroy record boundaries. |
| Small nodes | Prefer the host's established syslog convention for syslog_ident; avoid parallel local-file retention unless it has an explicit purpose and size limit. |
{.full-width}

## Pigsty {#pigsty}

Values use the fixed 8-vCPU, 32-GiB, 100-GiB SSD fixture and render the current Pigsty templates for PG19 Beta 3; this does not assert current Pigsty support for that historical or beta release.

| Template | Effective value | Versus upstream boot | Source expression |
| --- | --- | --- | --- |
| OLTP | Unmodified | — | — |
| OLAP | Unmodified | — | — |
| CRIT | Unmodified | — | — |
| TINY | Unmodified | — | — |
{.full-width}

> [!CAUTION]
> **Advice — pending human review.** Fact from the current Pigsty template projection: OLTP: PG9.0–19 Beta 3 unmodified; OLAP: PG9.0–19 Beta 3 unmodified; CRIT: PG9.0–19 Beta 3 unmodified; TINY: PG9.0–19 Beta 3 unmodified. No Pigsty-specific rationale is inferred from an absent override.

## Common pitfalls {#common-pitfalls}

- Editing syslog_ident without reloading configuration and verifying the effective value and subsequent behavior.
- Changing PostgreSQL framing or identifiers without testing the host daemon and remote receiver as one pipeline.
- Assuming syslog preserves unlimited message size, multiline boundaries, ordering, or repeated records by default.
- Changing syslog_ident globally without a rollback plan and a client or operational compatibility test.

## Related parameters {#related-parameters}

[`log_destination`](/parameters/log-destination/) · [`syslog_facility`](/parameters/syslog-facility/) · [`syslog_sequence_numbers`](/parameters/syslog-sequence-numbers/) · [`syslog_split_messages`](/parameters/syslog-split-messages/) · [`logging_collector`](/parameters/logging-collector/)

## References {#references}

- [PostgreSQL 19 Beta 3 — syslog_ident](https://www.postgresql.org/docs/19/runtime-config-logging.html#GUC-SYSLOG-IDENT)
- [PostgreSQL 19 release notes](https://www.postgresql.org/docs/19/release-19.html)
- [Machine-readable GUC export](/data/guc.jsonl)