Sailfish vs Releem: MySQL history or MySQL tuning

Releem is a hosted MySQL tuning service. An open-source agent on your database server, or beside it for RDS, sends metrics and query statistics to Releem's cloud, which recommends configuration changes and indexes and can apply them for you. Sailfish is a Laravel package that runs inside your application, keeps the history of MySQL's performance_schema counters in your own database, and sends an event when they change.

Both read performance_schema, so they overlap on questions like which queries cost the most and which indexes go unused. They differ on what they do with the answer. This page describes Releem as of November 2026.

Two different jobs#

Releem's job is tuning. Its configuration tuning covers "over 40 MySQL configuration parameters", worked out from your workload and applied from its portal or on a schedule, with a history that compares the server before and after each change. Its query optimization reviews your top 100 queries and top 100 slowest ones each week and writes the CREATE INDEX statements that would help them. You apply those yourself, unless you turn on its automatic schema changes, which are off by default.

Sailfish's job is memory. performance_schema only counts since the server started, so a restart or a failover wipes the answer to "is this index still used?" Sailfish stores what moved in every five-minute interval and keeps a rolled-up copy for good: hourly after seven days, daily after ninety. Its events compare the last hour with the same hour on each of the previous seven days. It does not tune configuration, and it changes nothing on the server: the SQL it shows, to drop a redundant index or turn on an instrument, is yours to run.

At a glance#

Where Releem is the better answer#

A server nobody has tuned. On a MySQL server still running its default buffer pool and log sizes, configuration is usually the biggest win available, and Releem is built to find it. Sailfish will show you buffer pool misses and temporary tables written to disk, and leave the setting to you.

Fixing a particular slow query. Releem reads the query's EXPLAIN plan and writes the index that would help it. Sailfish tells you that an index stopped being read or that a table started being scanned, and the query work after that is yours.

More than one stack, or more than MySQL 8.0. Releem's agent works at the server level, so it does not care what language talks to the database, and it covers MariaDB, Percona Server, PostgreSQL and MySQL back to 5.5. Sailfish needs a Laravel 12 or 13 application to run in and reads MySQL 8.0 only. It does see every client's traffic on that server, because performance_schema does.

The machine as well as the database. Releem charts CPU, memory, swap and IOPS next to the database metrics. Sailfish reads MySQL and nothing else.

Where Sailfish is the better answer#

History that survives a restart. Releem's Query Analytics docs say it counts each query's executions "since the last server restart". Sailfish keeps the last time each index was read, and when each table was last scanned, across restarts, and marks each restart on the charts. Releem's docs describe no per-index last-used date or reads timeline.

Alerts about change, wherever your team reads them. Sailfish's surges compare the last hour with the same hour on the previous seven days, for scans on each table, row-lock time, slow queries, errors by number and the share of transactions rolled back. An urgent one is sent as it opens and repeated every six hours until somebody acknowledges it, and its recovery says how long it lasted. Mail and Slack are built in, and a JSON webhook reaches PagerDuty or your own tools. As of November 2026, the notifications Releem documents are emails.

Nothing leaves your infrastructure. Sailfish reads performance_schema over your application's own connection and writes its history to sailfish_* tables beside yours. Releem's FAQ lists what its agent sends, which includes table and index names with their usage statistics, and query statistics with a query example and EXPLAIN plans. Storing that data in the EU is offered to customers with more than 20 instances, or case by case.

Fewer privileges. Sailfish needs SELECT on performance_schema. Releem's query optimization asks for SELECT on *.*, which it needs to run EXPLAIN on your queries, and applying configuration needs SYSTEM_VARIABLES_ADMIN.

Paying once. Releem's Starter plan is $39 a month for one server, billed annually, which is $468 a year. Sailfish is a one-time purchase per application.

One limit they share#

MySQL 8.0 gives no statement digest to queries sent as native prepared statements, and Laravel's MySQL connection sends them that way by default. Releem's docs say this keeps those queries out of its Query Analytics and recommend turning on PDO::ATTR_EMULATE_PREPARES. Sailfish's statement digests need the same setting. Its index and table counters, and every one of its events, see every statement either way.

Can you run both?#

We would expect so, though we have not certified the pairing. Both read performance_schema without changing it, and Sailfish takes a fresh baseline whenever a counter goes backwards, whatever reset it. The overlap is small: Releem would tune the server and suggest indexes, and Sailfish would keep the long history and send the alerts. If Releem applies a configuration change, Sailfish's Server page shows the effect on buffer pool misses and temporary tables in the weeks after.

Choosing between them#

If your question is "is this server configured well?", or you want somebody to write the index for a slow query, that is Releem's job. If your question is "what changed?", such as which index went cold since the last deploy or when a table started being scanned, you need a history that outlives the server's uptime, and that is the one Sailfish keeps.