HP OpenVMS 8.x manual Buffersize

The following steps are necessary to set up the InfoServer software on the designated system:

1.Copy SYS$STARTUP:ESS$LAD_STARTUP.TEMPLATE to ESS$LAD_STARTUP.DAT (save the ESS$LAD_STARTUP.TEMPLATE file as a backup).

2.Edit SYS$STARTUP:ESS$LAD_STARTUP.DAT to modify parameters as needed. This file

configures InfoServer parameters affecting the OpenVMS LASTport/Disk™ (LAD) server, which allows access to the DVD drive. The following is an example of the configuration file (with default settings):

!++

!ESS$LAD_STARTUP.TEMPLATE

!Copy this file to SYS$STARTUP:ESS$LAD_STARTUP.DAT and edit it

!to suit your local situation.

!

!This file is used by SYS$STARTUP:ESS$LAD_STARTUP.COM to set up

!the parameters for the InfoServer Application on OpenVMS

!LASTport/Disk (LAD) server.

!

!Note:

!The LAD disk block cache is structured as a number of fixed-size

!buckets. You must specify both the bucket size and the number of

!buckets for the cache.

!

!The LAD cache is allocated from non-paged pool and is in no way

!associated with the XFC cache. The total LAD cache size in bytes

!may be determined by the formula:

!

!cache-bytes = bucket-size-in-blocks * number-of-buckets * 512

!Be sure the SYSGEN parameters NPAGDYN/NPAGEVIR are sized appropriately.

!The following keywords with values are accepted by this procedure:

!

!BUFFER_SIZE - A number between 3 and 8 denoting the

!	bucket size in blocks as follows:
!	3	-	8	blocks
!	4	-	16	blocks
!	5	-	32	blocks
!	6	-	64	blocks
!	7	- 128 blocks
!	8	- 256 blocks

!CACHE_BUCKETS - Number of buckets

!MAXIMUM_SERVICES - Maximum number of services (max=1024)

!WRITE_LIMIT - Server wide count of asynchronous writes

!--

BUFFER_SIZE	=	3	! default (8 block buckets)
CACHE_BUCKETS		= 512	! Default setting
WRITE_LIMIT	=	0	! No async writes
MAXIMUM_SERVICES = 256			! default (typically more than enough)

The following table provides a short description of each of the parameters:

Parameter	Description
BUFFER_SIZE	The InfoServer block cache is structured as an array of fixed-size buffers (also called
	buckets). The BUFFER_SIZE parameter determines the size of each buffer or bucket.
	The numeric value of this parameter is an integer in the range 3 through 8,
	representing the bucket size in 512-byte blocks as follows. Note that bucket sizes
	larger than 32 blocks might not be appropriate for most users. The OpenVMS client
	segments I/O requests larger than 31 blocks into 31-block chunks, which could
	result in excessive I/O activity to the disk. The cache is allocated from nonpaged
	pool and is dedicated solely to the LAD driver.
	3	8 blocks (default)
	4	16 blocks
	5	32 blocks

194 Setting Up and Performing Network Booting