Specifies the maximum number of databank files that the database server can have open at any one time. Specifies the maximum number of tables that can be accessed simultaneously by the database server. Specifies the maximum number of transactions that can be active in the database server. Initial size of the SQLPool area in K bytes. This area contains information about each session, i.e. opened tables and databanks, compiled SQL programs, etc. The SQLPool area will expand automatically if it is too small, but it will not be larger than MaxSQLPool. The number of threads in the database server that can serve client requests. The number of background threads in the database server. The maximum number of users that are allowed to connect to the database server. This parameter should not exceed the number of users specified in the Mimer SQL license key.This number is also used to calculate the size of the shared memory region used for local database server communication. About 70 Kbytes of shared memory will be allocated for each user. A number which specifies what kind of check that should be performed when a databank is opened which previously was not closed properly.Index pages only are checked in the foreground while applications that access the databank waits for the operation to complete.A full databank check (involving index and data pages) provides for more secure operations, but may take much longer to execute than an index page check. When a full check is done, the index pages are checked in the foreground and the data pages are checked in the background so there is a smaller effect on performance.This options performs no checking when the file is opened. The system still verifies the integrity of each page through a checksum. A few pages may have been pre-allocated and these are not reclaimed when this option is used. If the option is subsequently changed these pages will be reclaimed the next time the databank is opened.This option performs a check of all index pages in the databank in the background. This is done concurrently with other operations on the system.This option performs a check of all pages in the databank in the background. This is done concurrently with other operations on the system.The Immediate restart options require a license key called "Imm Restart".Databank checks can be avoided by always shutting down the database server properly with the
MIMCONTROLcommand, especially prior to shutting down the machine.
The number of 4 Kbytes pages in the bufferpool area containing pages from the databank files. The default value of this parameter is 12.5% of the total RAM memory in the machine.VMS: There may be an OpenVMS limit set for the amount of memory a process may allocate, this limit will not be exceeded. Among the various OpenVMS parameters, WSMAX is likely to be of primary interest in connection with this limit. The number of 32 Kbytes pages in the bufferpool area containing pages from the databank files. The default value of this parameter is 8.33% of the total RAM memory in the machine. The number of 128 Kbytes pages in the bufferpool area containing pages from the databank files. The default value of this parameter is 5% of the total RAM memory in the machine. This option controls how quickly a transaction commit is secured on disk. It greatly affects the performance of the database server. For example, if a single user commits two transactions in quick sequence the database server may use a single I/O to secure both transactions when delayed commit is on.Transactions are never reordered by using the delayed commit option. I.e. it is not possible for a later transaction to be secured on disk before an earlier one. The database is thus always returned to a consistent state after a machine crash. However, if a transaction has been committed but not yet written to disk it will be lost if the database server or machine goes down in an uncontrolled fashion.Transactions that use the XA transaction protocol are automatically committed with delay commit disabled.Dealyed commit option can be set to one of the following:In this mode delayed commit is not used unless a transaction is set to use delayed commit by the application. This is the default.In this mode all transactions where the delay mode has not been explicitly set are delayed. The transaction will be secured within the timeout period specified. If other transactions are committed before the timeout occurs the transacations may be combined into a single I/O to boost performance.In this mode all transactions are secured to disk immediately and the application will not regain control after a commit until the transaction has been secured. This option overrides any application settings for delay commit. This specifies the number of milliseconds to wait before the transaction is written to disk. If a value of zero is specified transactions are not flushed until the server determines that the commit set page is full. In general, this is not recommended as transactions are likely to be lost if there is an uncontrolled machine stop.Default is 100 milliseconds. Enable password login:
0 - password login disabled. (Only
1 - password login allowed.
This parameter gives a list of host system users, i.e. operators, or e-mail addresses that should receive e-mail notification of serious problems with the database server.VMS: On OpenVMS, you can also specify
OPER.This will enable that notification messages are sent to the central operator, i.e. processes that have set:$ REPLY/ENABLE=CENTRAL.
This parameter may specify an alternate path for the dump directories. The default is to create dump directories under the database home directory. Specifies how the database server should handle incoming TCP/IP connection requests. If this parameter is set to
-(a single dash), the TCP/IP capability will be disabled for the database server.Linux: On Linux, the
TCPPortparameter is, by default, set to
inetdwhich means that the TCP/IP port server program,
mimtcp, will be used for establishing a connection to any Mimer SQL database server (of version 8 and later). In this case clients may connect to the port to which
mimtcplistens, usually 1360, and the handshake will be passed over to the requested Mimer SQL database server.If a TCP/IP port number is specified, the database server will listen directly to that port.VMS: On OpenVMS, the
TCPPortparameter is, by default, set to the TCP/IP port number
1360. The TCP/IP port server program,
MIMTCP, will automatically be started to listen to the given port, serving all Mimer SQL database servers (of version 8 and later) set up to use that port.
The maximum size (in kilobytes) of the SQLPool. The SQLPool memory area grows dynamically, but the size will never exceed this parameter. Use this parameter to control the maximum virtual size (maximum page file usage) for the database server process. A number which specifies whether the bufferpool and communication buffers should be locked in memory (1) or not locked in memory (0). Small bufferpool dump (no page content).
0 = No
1 = Yes (default)
Linux: By default, this parameter is set to 1 which indicates that the database should be started automatically when the operating system goes into multi-user mode. If the parameter is set to 0 the database will not be started automatically. Linux: If the database server goes into an erroneous and unrecoverable state, it will produce dumps of the current internal database structures before it goes down. If this situation occurs, it is of great importance for the error detection process to get a Linux kernel stack trace from the location where the error was located.By defining this parameter to a command that can produce a kernel trace, such as
pstack, stack information will be automatically generated to
%poption, used in the example above, is used to get the current process ID as a parameter to the command given.
VMS: Specifies the DECNET network object that the database server listens to. Each database server must use a unique network object. The default value is the database name.If you set this parameter to
-(a single dash), the DECNET capability will be disabled for the database server.
VMS: This parameter specifies the process name prefix for the database server. (The last part of the process name is always
Srv).Specify a maximum of 11 characters. The default value is to use the first 11 characters of the database name.
VMS: This parameter specifies the number of users who can access the database through a network connection.The value used by the system will be the minimum of this parameter and the
Usersparameter. The default value is 5000.Since the
Usersparameter can not be larger than 5000, this means that all users may be network users.
VMS: This parameter specifies the OpenVMS priority for the database server process. Linux: Specifies if the background threads should run at a higher priority than other server threads. During certain circumstances like in situations where the background threads cannot manage to shorten a transaction queue this can be an alternative. VMS: Specifies the time (in seconds) between the cleanup sweeps that check for terminated database clients. Linux: The number of threads in the database server that can serve I/O requests. This parameter is only present and used for some Linux implementations (if it is not present in a default generated multidefs file, the most common reason is that the native Asynchronous I/O is used.) VMS: If the
BPResidentparameter is blank (default) the bufferpool will be allocated in normal process memory and is backed by the paging file. The paging file process quota for the database server will be increased accordingly.If the
BPResidentparameter specifies a name, a memory resident global section with this name will be created to hold the buffer pool. Since physical memory is used, the buffer pool will not be backed by the paging file. Also, the working set quota of the process does not have to include the buffer pool. This is recommended for larger buffer pools.To use the
BPResidentparameter, the user that starts the database server must hold the
VMS$MEM_RESIDENT_USERprocess right.Please see the VMS Guide for more information.
VMS: Multithread can be used to limit the number of kernel threads used by a database server. When running several instances of Mimer servers on a machine with a large number of cores, it can be beneficial to limit the number of kernel threads (and the number of cores) each database server can use.The default value is zero which means that the number of kernel threads are not limited.This feature requires OpenVMS 8.4 or later. This option decides which Mimer SQL database server program that should be started to operate the database files for the database:Linux: 0 - mimengine
The traditional Mimer SQL Engine server.1 - mimmobile
This database server is used in small footprint environments and is only provided in specific Mimer SQL distributions. The server is using the Mimer SQL Engine SQL compiler.2 - mimmicro
This database server is usually used in extreme small footprint environments and is only provided in specific Mimer SQL distributions.3 - mimexper
The new Mimer SQL Experience server. This is usually the default alternative when installing a new database server.4 - mimmobex
This database server is used in small footprint environments and is only provided in specific Mimer SQL distributions. The server is using the new Mimer SQL Experience SQL compiler.VMS: 3 - mimexper
The new Mimer SQL Experience server. This is usually the default alternative when installing a new database server.
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