Read-only mode

Read-only mode for a connection disables any table or global modifications. Therefore, queries like create, drop, various types of alter, attach, optimize, and data modification queries such as insert, replace, delete, update, and others will all be rejected. Changing daemon-wide settings using SET GLOBAL is also not possible in this mode.

However, you can still perform all search operations, generate snippets, and run CALL PQ queries. Additionally, you can modify local (connection-wide) settings.

To check if your current connection is read-only or not, execute the show variables like 'session_read_only' statement. A value of 1 indicates read-only, while 0 means not read-only (usual).

Activation

Typically, you define a separate listen directive in read-only mode by adding the suffix _readonly to it. However, you can also do this interactively for the current connection by executing the SET ro=1 statement via SQL.

Deactivation

If you're connected to a VIP socket, you can execute SET ro=0 (even if the socket you are connected to was defined as read-only in the config and not interactively). This will switch the connection to the usual (not read-only) mode with all modifications allowed.

For standard (non-VIP) connections, escaping read-only mode is only possible by reconnecting if it was set interactively, or by updating the configuration file and restarting the daemon.

⪢ Logging

Query logging

Query logging can be enabled by setting the query_log directive in the searchd section of the configuration file.

Queries can also be sent to syslog by setting syslog instead of a file path. In this case, all search queries will be sent to the syslog daemon with LOG_INFO priority, prefixed with [query] instead of a timestamp. Only the plain log format is supported for syslog.

‹›
  • Config
Config
📋
searchd {
...
    query_log = /var/log/query.log
    query_log_format = sphinxql # default
...
}

Logging format

Two query log formats are supported:

  • sphinxql (default): Logs in SQL format. It also provides an easy way to replay logged queries.
  • plain: Logs full-text queries in a simple text format. Recommended if most of your queries are primarily full-text, or if you don't care about non-full-text components of your queries, such as filtering by attributes, sorting, grouping, etc. Queries logged in the plain format cannot be replayed.

To switch between the formats, you can use the searchd setting query_log_format.

SQL log format

The SQL log format is the default setting. In this mode, Manticore logs all successful and unsuccessful select queries. Requests sent as SQL or via the binary API are logged in the SQL format, but JSON queries are logged as is. This type of logging only works with plain log files and does not support the 'syslog' service for logging.

‹›
  • Config
Config
📋
query_log_format = sphinxql # default

The features of the Manticore SQL log format compared to the plain format include:

  • Full statement data is logged where possible.
  • Errors and warnings are logged.
  • The query log can be replayed.
  • Additional performance counters (currently, per-agent distributed query times) are logged.
  • Each log entry is a valid Manticore SQL/JSON statement that reconstructs the full request, except if the logged request is too large and needs to be shortened for performance reasons.
  • JSON requests and additional messages, counters, etc., are logged as comments.
‹›
  • Example
Example
📋
/* Sun Apr 28 12:38:02.808 2024 conn 2 (127.0.0.1:53228) real 0.000 wall 0.000 found 0 */ SELECT * FROM test WHERE MATCH('test') OPTION ranker=proximity;
/* Sun Apr 28 12:38:05.585 2024 conn 2 (127.0.0.1:53228) real 0.001 wall 0.001 found 0 */ SELECT * FROM test WHERE MATCH('test') GROUP BY channel_id OPTION ranker=proximity;
/* Sun Apr 28 12:40:57.366 2024 conn 4 (127.0.0.1:53256) real 0.000 wall 0.000 found 0 */  /*{
    "index" : "test",
    "query":
    {
        "match":
        {
            "*" : "test"
        }
    },
    "_source": ["f"],
    "limit": 30
} */

Plain log format

With the plain log format, Manticore logs all successfully executed search queries in a simple text format. Non-full-text parts of queries are not logged. JSON queries are logged as flattened to a single line.

‹›
  • Config
Config
📋
query_log_format = plain

The log format is as follows:

[query-date] real-time wall-time [match-mode/filters-count/sort-mode total-matches (offset,limit) @groupby-attr] [table-name] {perf-stats} query

where:

  • real-time is the time from the start to the finish of the query.
  • wall-time is similar to real-time, but excludes time spent waiting for agents and merging result sets from them.
  • perf-stats includes CPU/IO stats when Manticore is started with --cpustats (or it was enabled via SET GLOBAL cpustats=1) and/or --iostats (or it was enabled via SET GLOBAL iostats=1):
    • ios is the number of file I/O operations carried out;
    • kb is the amount of data in kilobytes read from the table files;
    • ms is the time spent on I/O operations.
    • cpums is the time in milliseconds spent on CPU processing the query.
  • match-mode can have one of the following values:
    • "all" for SPH_MATCH_ALL mode;
    • "any" for SPH_MATCH_ANY mode;
    • "phr" for SPH_MATCH_PHRASE mode;
    • "bool" for SPH_MATCH_BOOLEAN mode;
    • "ext" for SPH_MATCH_EXTENDED mode;
    • "ext2" for SPH_MATCH_EXTENDED2 mode;
    • "scan" if the full scan mode was used, either by being specified with SPH_MATCH_FULLSCAN or if the query was empty.
  • sort-mode can have one of the following values:
    • "rel" for SPH_SORT_RELEVANCE mode;
    • "attr-" for SPH_SORT_ATTR_DESC mode;
    • "attr+" for SPH_SORT_ATTR_ASC mode;
    • "tsegs" for SPH_SORT_TIME_SEGMENTS mode;
    • "ext" for SPH_SORT_EXTENDED mode.

Note: the SPH* modes are specific to the sphinx legacy interface. SQL and JSON interfaces will log, in most cases, ext2 as match-mode and ext and rel as sort-mode.

‹›
  • Example
Example
📋
[Fri Jun 29 21:17:58 2021] 0.004 sec [all/0/rel 35254 (0,20)] [lj] [ios=6 kb=111.1 ms=0.5] test
[Fri Jun 29 21:17:58 2021] 0.004 sec [all/0/rel 35254 (0,20)] [lj] [ios=6 kb=111.1 ms=0.5 cpums=0.3] test
[Sun Apr 28 15:09:38.712 2024] 0.000 sec 0.000 sec [ext2/0/ext 0 (0,20)] [test] test
[Sun Apr 28 15:09:44.974 2024] 0.000 sec 0.000 sec [ext2/0/ext 0 (0,20) @channel_id] [test] test
[Sun Apr 28 15:24:32.975 2024] 0.000 sec 0.000 sec [ext2/0/ext 0 (0,30)] [test] {     "index" : "test",     "query":     {         "match":         {             "*" : "test"         }     },     "_source": ["f"],     "limit": 30 }

Logging only slow queries

By default, all queries are logged. If you want to log only queries with execution times exceeding a specified limit, the query_log_min_msec directive can be used.

The expected unit of measurement is milliseconds, but time suffix expressions can also be used.

‹›
  • Config
Config
📋
searchd {
...
    query_log = /var/log/query.log
    query_log_min_msec  = 1000
    # query_log_min_msec  = 1s
...
}

Log file permission mode

By default, the searchd and query log files are created with permission 600, so only the user under which Manticore is running and root can read the log files. The query_log_mode option allows setting a different permission. This can be helpful for allowing other users to read the log files (for example, monitoring solutions running on non-root users).

‹›
  • Config
Config
📋
searchd {
...
    query_log = /var/log/query.log
    query_log_mode = 666
...
}