HP Tru64 UNIX and TruCluster Server Version 5.1B-5 Patch Summary and Release Notes (March 2009)

1 Enhancements, Improvements, and Features
This chapter describes key new features, enhancements, and improvements delivered
in Version 5.1B-5.
1.1 Performance Improvement for TCP Applications
The TCP selective acknowledgment feature is enabled by default. When the selective
acknowledgments feature is enabled, the data receiver can inform the sender about all
the segments that were received successfully, so that the sender needs to retransmit
only those segments that were lost. This improves the performance of TCP applications
on a network which is experiencing packet loss.
1.2 Support for 2 TB LUNs
This kit enhances the Tru64 UNIX CAM (Call Applications Manager ) subsystem to
support a LUN size of upto 2 TB from the previous maximum limit of 1 TB. This allows
Tru64 UNIX to take advantage of the increased LUN size supported by the storage
arrays.
1.3 Dynamic Pathing in Disk Driver
This kit enhances the CAM disk driver to dynamically recognize and use newly added
paths while the device is in use.
The new behavior will now dynamically recognize and use new paths while the device
is in use, thereby making all the paths available for I/O.
Before Version 5.1B-5, the disk driver used all paths that were available at open/mount
time. Paths added after would not be added to the active set until a close/open or
dismount/mount occurred.
1.4 Enhancements to binary.errlog
This kit enhances the error log feature to improve user experience. In some error
situations, the entries appear to be missing time sequences within the binary.errlog
file, which makes it difficult to determine if the system did not have any events to log
or there was some issue (such as low disk free space) that disabled event reporting for
a period of time.
This kit introduces the following additional enhancements to binary.errlog file:
1. Introduce a set of markers in the binary.errlog file frame work to track the
events occurring in the CAM layer and log the most recent log that was attempted
on the system.
2. Increase the internal buffer .blbuf through the sysconfigtab variable, if
necessary.
1.1 Performance Improvement for TCP Applications 17