Eloquence A.06.20 / Release Notes
- Server Configuration changes
- HTTP Performance display
- On-line backup
- dbctl command line interface to eloqdb6
Server Configuration changes
The following configuration changes are present in the eloqdb6.cfg
configuration file. When updating from a previous Eloquence
version, please review the new eloqdb6.cfg configuration template file
and merge relevant changes manually to your current eloqdb6.cfg
configuration file.
On the HP-UX and Linux platforms, the eloqdb6.cfg configuration file
is located at /etc/opt/eloquence6/eloqdb6.cfg
The default eloqdb6.cfg configuration file is located at
/opt/eloquence6/newconfig/config/eloqdb6.cfg
On the Windows NT platform, the eloqdb6.cfg configuration file
is located at <Installation Directory>/etc/eloqdb6.cfg
The default eloqdb6.cfg configuration file is located at
<Installation Directory>/etc/eloqdb6.cfg.sam
Please note: On the HP-UX and Linux platform, the eloqdb6
I/O processes or kernel threads are visible by ps.
So instead of a single eloqdb6 you will have 5 eloqdb6 processes
running by default. This is normal.
[server] section
Title = "Title"
If set, a server title is displayed by the ps program in
the eloqdb6 command line instead of the default "eloqdb6: active".
If you are using multiple eloqdb6 server processes on a single
system this can be used to distinguish between different
server instances. The default value is empty.
This configuration is ignored on the Windows NT platform.
NoDNS = {0|1}
If set, no reverse DNS lookup is performed on connection to
the eloqdb6 server. A broken DNS configuration or a slow DNS
server could lead to long connection times. Default value is 0.
DisableScan = {0|1}
If set, the eloqdb6 scan API (which is used to accelerate
the FIND/SORT command and used by SQL/R) is disabled.
The only reason to set this configuration item is to track
a possible problem in the FIND/SORT command (which then falls
back to the older, much slower access strategy).
The default value is 0.
SyncMode = {0|1}
If set (the default), this causes the eloqdb6 server to
operate in sync write mode. The sync write mode is more
resistent against operating system and hardware failures.
When sync mode is disabled (set to 0) the eloqdb6 uses the
faster async write strategy which performs fewer disk writes
but could lead to a damaged database environment in case of
a system failure. The default value is 1.
With the previous Eloquence versions the write mode was
specified using the dbvolchange command line utility
(dsync, lsync flags). Specifying this setting in the server
configuration make this important option more accessible.
HTTPUser = "user name"
The eloqdb6 server is able to display status information by
supporting the HTTP protocol (you can use Netscape to monitor
the database server process).
If set, the eloqdb6 HTTP status display will require a
matching user name (HTTP basic authentification) before allowing
access to the eloqdb6 HTTP status. The default value is empty.
HTTPPswd = "pswd"
If set, the eloqdb6 HTTP status display will require a
matching password (HTTP basic authentification) before allowing
access to the eloqdb6 HTTP status. The default value is empty.
Please note: Unless the eloqdb6.cfg file is secured against access
from ordinary users this is not secure. Please don't use a password
which gains access to administrative accounts on the system as
users could use it to get unauthorized access to the system.
Since the HTTP status display only provides read-only access
to the database status and poses a very limited security risk
it might not worth the trouble.
HTTPFrame = {0|1}
If set, no link information is output on the HTTP status display.
So the status page could be used in a web frame.
Default value is 0.
This setting was defined in the [config] section in previous versions.
[config] section
IOThreads = number of threads
This specifies the number of I/O threads which are used by eloqdb6.
eloqdb6 uses either separate processes or kernel threads to perform
overlapped I/O operations. Please note that the eloqdb6 I/O threads
are visible with the ps command.
Default value is 4. A zero value disables usage of IO threads.
This configuration setting only effects the UNIX platform.
On Windows NT, the overlapped I/O is provided by the operating system.
AllowSecondaryBlockingLock = {0|1}
If set, secondary blocking locks are allowed. Normally, secondary
locks in a blocking mode (odd modes) will fail with database
status -135 ("Second lock is not allowed in modes 1,3,5,11,13 and 15.")
instead of blocking. Enabling this setting could result in a deadlock
in the eloqdb6 server when programs use an incompatible lock strategy.
Previous Eloquence versions disallow secondary blocking locks.
Default value is 0.
VnodeCache
This configuration item is obsolete. The value is now adjusted
dynamically by the eloqdb6 server. The item is still
accepted to allow backward compatibility.
VbufElements
This configuration item is obsolete. The value is now adjusted
dynamically by the eloqdb6 server. The item is still
accepted to allow backward compatibility.
HTTPFrame
This setting has been moved to the [server] section. In the [config]
section, it is still accepted to allow backward compatibility.
SyncerMinFree
This configuration item is obsolete. The syncer thread now uses a
modified strategy where this parameter is not used anymore.
The item is still accepted to allow backward compatibility.
SyncerNFlush
This configuration item is obsolete. The syncer thread now uses a
modified strategy where this parameter is not used anymore.
The item is still accepted to allow backward compatibility.
[devices] section
This section defines the "server devices" which can be used
with dbstore and dbrestore. Each entry consists of the device name
and an associated path.
A "server device" could either be a single file, a directory or a
device. When no server devices are configured, dbstore and dbrestore
operation is refused by the server.
The example below defines two server devices. The device "tape"
points to a tape device file, the device "backup" points to a directory
which is intended to hold the backup files.
[devices]
Tape = /dev/rmt/c1t0d0BEST
Backup = /data/backup
Please refer to the Database Backup
document for more information on server devices.
HTTP Performance monitor
A performance page has been added to the eloqdb6 HTTP status display
which provides information on the server load and disk activities.
Status values are available for the last ten minutes and an overall
value since server start (example).
The following information is present:
- server load
- What percentage of time was spent serving requests vs.
waiting on new requests. A low server load indicates that
the server is waiting for the clients most of the time.
- client requests
- Number of client requests per second.
- committed transactions
- Number of committed transactions per second.
- disk read requests
- Number of disk read requests per second.
- disk write requests
- Number of disk write requests per second.
- disk sync requests
- Number of disk sync requests per second.
In addition, the statistics HTTP status page has been enhanced
to include disk performance information (avg. time per disk access)
and the on the percentage of overlapped vs. non-overlapped disk
accesses (example).
On-line backup
The Eloquence A.06.20 database supports on-line backup.
A backup can be made while the database is active. Clients can access
and modify the database (at reduced performance).
Previous Eloquence A.06.xx versions required that the eloqdb6
server was terminated.
The on-line backup is initiated with the dbctl backup start
command which causes the eloqdb6 process to enter on-line backup mode.
In on-line backup mode, no changes are made to the data volume(s)
and an arbitrary backup tool could be used to backup the
data volume(s).
All changes are temporarily saved in the log volume(s) and are
copied to the data volume(s) once the on-line backup mode has
been finished with the dbctl backup stop command.
A detailed description how to backup your Eloquence database is
available in the
Database backup document.
dbctl command line interface to eloqdb6
dbctl is a new tool which allows access to a running eloqdb6 process.
It can be used to retrieve eloqdb6 status information (which could be
used in a script) or to manage some aspects of the eloqdb6 process
(eg. shut down the server or control the on-line backup).
The eloqdb6 HTTP status display provides a more convenient interface
to the eloqdb6 server status, but is harder to use from a script
file. The dbctl utility intends to fill that gap and provides
a convenient interface to text based tools.
For more information, please refer to the
Database on-line utilities document.
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