Welcome
Administering
In addition to administering the database server, you can tune performance, replicate data, and archive data.
System administration
These topics contain concepts, procedures, and reference information for database and database server administrators to use for managing and tuning HCL Informix® database servers.
Administrator's Reference
The HCL® Informix® Administrator's Reference includes comprehensive descriptions of HCL Informix configuration parameters, the system-monitoring interface (SMI) tables in the sysmaster database, the syntax of database server utilities such as onmode and onstat, logical-log records, disk structures, event alarms, and unnumbered error messages.
Administrative Utilities
The onmode utility
Use the onmode utility to change the database server operating mode and perform various other operations on shared memory, sessions, transactions, parameters, and segments.
onmode -wf, -wm: Dynamically change certain configuration parameters
Use the onmode -wf or onmode -wm command to dynamically change specific configuration parameters.
onmode -wm: Change LRU tuning status
You can use the onmode -wm option to change the LRU tuning status without updating the onconfig file.

HCL Informix® V15.0.0 documentation
Welcome to the documentation for HCL Informix® 15.0.0 and related client tools and products.
Product overview
HCL Informix® is a fast and scalable database server that manages traditional relational, object-relational, and dimensional databases. Its small footprint and self-managing capabilities are suited to embedded data-management solutions.
Installing
These topics describe how to install HCL Informix® database servers, client products, and modules.
Administering
In addition to administering the database server, you can tune performance, replicate data, and archive data.
- System administration
  These topics contain concepts, procedures, and reference information for database and database server administrators to use for managing and tuning HCL Informix® database servers.
  - List of utilities
    HCL Informix® includes utilities and applications that you can use to perform administrative tasks and capture information about configuration and performance.
  - Administrator's Guide
    The HCL® Informix® Administrator's Guide provides the information required to administer HCL Informix.
  - Administrator's Reference
    The HCL® Informix® Administrator's Reference includes comprehensive descriptions of HCL Informix configuration parameters, the system-monitoring interface (SMI) tables in the sysmaster database, the syntax of database server utilities such as onmode and onstat, logical-log records, disk structures, event alarms, and unnumbered error messages.
    - Configuring and monitoring Informix®
    - Administrative Utilities
      - Overview of Utilities
        The Informix® database server utilities allow you to perform administrative tasks directly from the command line.
      - The finderr utility
        Use the finderr utility to view additional information on Informix® error messages. On UNIX™ and Linux™ platforms, the information appears on the command line. On Windows™ platforms, the information appears in the Error Messages program.
      - The genoncfg Utility
        Use the genoncfg utility to expedite the process of customizing the default Informix® configuration file (onconfig.std) to the host environment and your planned usage of a database server instance.
      - The ifxclone utility
        You use the ifxclone utility to create a server clone from a snapshot of an existing database server.
      - The oncheck Utility
        Use the oncheck utility to check specified disk structures for inconsistencies, repair inconsistent index structures, and display information about disk structures.
      - The onclean utility
        Use the onclean utility to force a shut down of the database server when normal shut down with the onmode utility fails or when you cannot restart the server. The onclean utility attempts to clean up shared memory, semaphores, and stops database server virtual processes.
      - The oncmsm Utility
      - The onconfig_diff utility
        Use the onconfig_diff utility to compare two onconfig files.
      - The ondblog utility
        Use the ondblog utility to change the logging mode for one or more databases.
      - The oninit utility
        The oninit utility starts the database server.
      - The onkstash Utility
        Use the onkstash utility to create a password stash file for an existing PKCS#12 keystore.
      - The onkstore Utility
      - The onlog utility
        The onlog utility displays the contents of a logical-log file, either on disk or on backup.
      - The onmode utility
        Use the onmode utility to change the database server operating mode and perform various other operations on shared memory, sessions, transactions, parameters, and segments.
        onmode command syntax
        Use onmode utility commands to perform various database server operations.
        onmode -a: Add a shared-memory segment
        onmode -BC: Allow large chunk mode
        onmode -c: Force a checkpoint
        onmode -C: Control the B-tree scanner
        Use the onmode -C command to control the B-tree scanner and specify information about B-tree scanner threads.
        onmode -cache surrogates: Cache the allowed.surrogates file
        onmode -d: Set data-replication types
        onmode -d: Set High Availability server characteristics
        onmode -d command: Replicate an index with data-replication
        onmode -D, -M, -Q, -S: Change decision-support parameters
        onmode -e: Change usage of the SQL statement cache
        onmode -F: Free unused memory segments
        Use the onmode -F command to free shared-memory segments that are unavailable or no longer needed for a process
        onmode -h: Update sqlhosts caches
        onmode -I: Control diagnostics collection
        Use the onmode -I option to start and stop diagnostics collection.
        onmode -k, -m, -s, -u, -j: Change database server mode
        onmode -l: Switch the logical-log file
        onmode -n, -r: Change shared-memory residency
        onmode -O: Override ONDBSPACEDOWN WAIT mode
        onmode -p: Add or drop virtual processors
        Use the onmode -p command to dynamically add or drop virtual processors for the database server instance. The onmode -p command does not update the onconfig file.
        onmode -P: Start, stop, or restart a listen thread dynamically
        Use the onmode -P command to start, stop, or restart an existing listen thread for a SOCTCP or TLITCP network protocol without interrupting existing connections.
        onmode -R: Regenerate .infos.dbservername File
        onmode -W: Change settings for the SQL statement cache
        onmode -we: Export a file that contains current configuration parameters
        Use the onmode -we command to create and export a configuration file that is a snapshot of your current configuration parameters.
        onmode -wf, -wm: Dynamically change certain configuration parameters
        Use the onmode -wf or onmode -wm command to dynamically change specific configuration parameters.
        onmode -wm: Change LRU tuning status
        You can use the onmode -wm option to change the LRU tuning status without updating the onconfig file.
        onmode -wi: Import a configuration parameter file
        Use the onmode -wi command to import a file that contains new values for multiple configuration parameters. If the parameters are tunable, which means they can be updated individually with an onmode -wm command, the database server applies the new values.
        onmode -Y: Dynamically change SET EXPLAIN
        onmode -z: Kill a database server session
        onmode -Z: Kill a distributed transaction
      - The onparams Utility
        Use the onparams utility to add or drop a logical-log file, change physical-log parameters, and add a new buffer pool.
      - onpassword Syntax
      - The onrestorept Utility
        You can use the onrestorept utility to restore the database server back to the state that it was in just before the start of the failed upgrade.
      - The onspaces utility
        Use the onspaces utility to manage the storage spaces in your database.
      - The onstat utility
        The onstat utility reads shared-memory structures and provides statistics about the database server at the time that the command runs.
    - SQL Administration API
    - Appendixes
  - DB-Access User's Guide
    The HCL® Informix® DB-Access User's Guide describes how to use the utility to access, modify, and retrieve information from HCL Informix database servers.
  - High-Performance Loader User's Guide
    The describes how to use the HCL Informix® to load and unload large quantities of data efficiently to or from Informix databases.
  - Performance Guide
    The HCL® Informix® Performance Guide describes how to configure and operate your HCL Informix database server to improve overall system throughput and to improve the performance of SQL queries.
  - SNMP Subagent Guide
    The describes the Simple Network Management Protocol (SNMP) and the software that you need to use SNMP to monitor and manage HCL Informix® database servers and databases.
  - InformixHQ Guide
    InformixHQ is a modern web console for visualizing, monitoring, and managing your Informix server instances. It is purpose built for ease-of-use, scaling out, and optimizing DevOps needs. It provides critical performance management capabilities, monitoring how key performance metrics are changing over time and tracking how efficiently Informix is running your workload even when you’ve stepped away from your screen. Its monitoring system feeds directly into a customizable alerting system so you can be immediately alerted via email, Twilio, or PagerDuty whenever an issue occurs on one of your Informix database server instances. InformixHQ is designed to be scalable to efficiently manage and monitor as many Informix database server instances as you need. Moreover, it's a tool that can be shared by the DBAs, the app developers, the ops engineers, and management and accessed from any desktop, laptop, or mobile device. InformixHQ is the centralized hub for graphical monitoring, alerting, and administration of your Informix database servers.
- Backup and Restore Guide
  The HCL® Informix® Backup and Restore Guide describes how to use the HCL Informix and ontape utilities to back up and restore database server data. These utilities enable you to recover your databases after data is lost or becomes corrupted due to hardware or software failure or accident.
- Enterprise Replication
  The describes the concepts of data replication using HCL Informix® Enterprise Replication, including how to design your replication system, as well as administer and manage data replication throughout your enterprise.
Migrating and upgrading
You can upgrade to the 15.0.0 release of HCL Informix® or migrate from other database servers to Informix. Upgrading is an in-place migration method that uses your existing hardware and operating system software. Some changes to the Informix database server can affect upgrading from a previous release.
Client APIs and tools
You can use the HCL Informix® implementation of client APIs to develop applications for Informix database servers.
Embedding Informix®
When you embed HCL Informix®, you can use enterprise-class high-availability and high performance with embeddability features such as easy programmability, a small disk and memory footprint, and silent deployment.
Extending Informix®
Beyond standard relational database objects, HCL Informix® can be extended to handle specialized data types, access methods, routines, and other objects. Informix includes many built-in extensions that are fully integrated in the database server. Informix also provides modules, which are packages of extended database objects for a particular purpose and that are installed separately from the database server. Alternatively, you can create your own user-defined objects for Informix.
Data warehousing
In addition to designing and implementing Informix® dimensional databases, you can use tools to create data warehouse applications and optimize your data warehouse queries.
Designing databases
The first step in creating a relational database is to construct a data model, which is a precise, complete definition of the data you want to store. After you prepare your data model, you must implement it as a database and tables. To implement your data model, you first select a data type for each column and then you create a database and tables and populate the tables with data. You can also implement fragmentation strategies and control access to your data.
JSON compatibility
You can use the popular JSON-oriented query language created by MongoDB to interact with data stored in HCL Informix®.
Security
You can secure your Informix® database server and the data that is stored in your Informix databases. You can encrypt data, secure connections, control user privileges and access, and audit data security.
SQL programming
You can use the HCL Informix® implementation of the SQL language to develop applications for Informix database servers.
Troubleshooting HCL Informix®
Several troubleshooting techniques, tools, and resources are available for resolving problems that you encounter in your HCL Informix® database server environment.

onmode -wm: Change LRU tuning status

You can use the onmode -wm option to change the LRU tuning status without updating the onconfig file.

Figure 1. Syntax:


Element	Purpose	Key considerations
-wm	Dynamically sets the value of the specified configuration parameter for the current session.	None.
`0`	Turns off automatic LRU tuning for the current session.	None.
`1`	Turns on automatic LRU tuning for the current session.	None.

This command has an equivalent SQL administration API function.