Installation guide

4.6.5 Logical Storage Manager .................................................4–38

4.6.5.1 LSM Sparse Plexes May Erroneously Mask an I/O

Failure .................................................................4–38

4.6.5.2 Restrictions with LSM root and swap Volumes ........4–38

4.6.5.3 Possible Problems Accessing Physical Block 0 with

LSM ...................................................................4–39

4.6.5.4 Using LSM with SWXCR-P(A/B) and SWXCR-

E(A/B) RAID Controllers ......................................4–39

4.6.5.5 Enabling LSM After Installation Requires Rebuilding

the Kernel ............................................................4–39

4.6.5.6 The volrootmir Script Supports Only LUN 0 on HSZ . 4–40

4.6.5.7 Using LSM rootvol Requires sysconﬁgtab Parameters . 4–40

4.6.5.8 Error While Dissociating a Preferred LSM Plex .......4–40

4.6.5.9 Presto Reset and Flush Operations May Cause System

Crash ..................................................................4–40

4.6.6 Mounting Associated Products CD-ROMs on Tru64 UNIX

Versions Other Than Version 4.0F ..................................4–41

5 Development Environment Notes

5.1 General Programming ................................................................5–1

5.1.1 The malloc Function Is Now Tunable for Better

Multithreaded Performance ............................................5–1

5.1.2 New DEC C Default Tuning Could Impact Applications That

Directly Map I/O Space .................................................5–2

5.2 Realtime Programming ..............................................................5–2

5.2.1 SA_SIGINFO Not Visible Under Certain Namespace

Conditions ...................................................................5–2

5.2.2 POSIX 1003.1b Synchronized I/O and File Truncation ........5–3

5.2.3 The fcntl() Function and F_GETFL with O_DSYNC File

Status ..........................................................................5–3

5.3 DECthreads (pthreads) ...............................................................5–3

5.3.1 Static Libraries ...............................................................5–3

5.3.2 Signal Handling ..............................................................5–3

5.3.3 Scheduling Behavior (Contention Scope) ...........................5–4

Contents ix