ChorusOS 5.0 Transition Guide

New Features and Tunables

This section describes the new features and tunables added in version 5.0 of the ChorusOS operating system, including the default settings of the features in both configuration environments.

New Features

The following table provides a list of the features added in version 5.0 and their default settings in both the Basic and Extended configuration profiles.

For more information on these features, see "Configuring and Tuning" in the ChorusOS 5.0 System Administrator's Guide.

Table 4-1 New Features and Their Default Settings


Feature	Basic Profile	Extended Profile
`BLACKBOX`	true	true
`CORE_DUMP`	false	false
`DEV_CDROM`	true	true
`DEV_DISK`	true	true
`DEV_NVRAM`	true	true
`IOM_DEV_MNGT`	true	true
`IPv6`	false	false
`ISOFS`	true	true
`OS_GAUGES`	false	false
`POSIX_REALTIME_SIGNALS`	true	true
`POSIX_SHM`	true	false
`SOLARIS_SYSEVENT`	false	false
`SYSTEM_DUMP`	false	false
`WDT`	false	false

Changed Features

The following table lists the features for which the default settings have changed in version 5.0 of the ChorusOS operating system.

Table 4-2 Features for Which the Default Settings Have Changed


Feature	Basic Profile	Extended Profile
`ROUND_ROBIN`	false	false
`ON_DEMAND_PAGING`	false	false
`RTMUTEX`	false	false
`SOFTINTR`	false	false
`VTIMER`	false	false
`IPC`	true	true
`IPC_REMOTE`	false	false
`LOCAL_CONSOLE`	true	false
`IOM_IPC`	false	false
`IOM_OSI`	false	false
`SCSI_DISK`	false	false
`FLASH`	true	true
`RAWFLASH`	true	true
`VTTY`	false	false
`FIFOFS`	false	false
`FS_MAPPER`	false	false
`UFS`	false	false
`NFS_SERVER`	false	false
`DYNAMIC_LIB`	true	true
`GZ_FILE`	false	true
`POSIX_MQ`	false	false
`POSIX_SHM`	true	false
`PPP`	false	false
`HOT_RESTART`	false	false
`DEBUG_SYSTEM`	true	true

New Tunables and Their Default Settings

The following table lists the tunables that are new in version 5.0 of the ChorusOS operating system, along with their default settings.

Table 4-3 New ChorusOS Tunables


Tunable	Description	Default Setting
`kern.mkstat.maxevents`	Maximum number of `MKSTAT` events	1024
`kern.systemdump.systemdumpSize`	System dump memory area size	0x20000
`kern.blackbox.maxBufferNumber`	Maximum number of circular buffers	2
`kern.blackbox.bufsize`	Size of each blackbox circular buffer (in Kb)	64
`kern.blackbox.maxFilterNumber`	Maximum fine-grained filters	64
`kern.blackbox.maxProcIdNumber`	Maximum proc ID filters	64
`kern.blackbox.kernelLogging`	Microkernel logging messages	0
`iom.persistentramdisk0`	Current size of persistent ramdisk 0	0
`iom.persistentramdisk1`	Current size of persistent ramdisk	0
`iom.persistentramdisk2`	Current size of persistent ramdisk 2	0
`iom.persistentramdisk3`	Current size of persistent ramdisk 3	0
`iom.persistentramdisk4`	Current size of persistent ramdisk 4	0
`iom.persistentramdisk5`	Current size of persistent ramdisk 5	0
`iom.persistentramdisk6`	Current size of persistent ramdisk 6	0
`iom.persistentramdisk7`	Current size of persistent ramdisk 7	0
`iom.persistentramdisk8`	Current size of persistent ramdisk 8	0
`iom.persistentramdisk9`	Current size of persistent ramdisk 9	0
`iom.persistentramdiska`	Current size of persistent ramdisk 10	0
`iom.persistentramdiskb`	Current size of persistent ramdisk 11	0
`iom.persistentramdiskc`	Current size of persistent ramdisk 12	0
`iom.persistentramdiskd`	Current size of persistent ramdisk 13	0
`iom.persistentramdiske`	Current size of persistent ramdisk 14	0
`iom.persistentramdiskf`	Current size of persistent ramdisk 15	0
`iom.wdt.defer`	Defer watchdog interrupt processing to C_OS interrupt thread	0
`iom.wdt.sysdump`	watchdog triggering system dump	0
`iom.wdt.period`	Internal period (in ms) of the watchdog timer	4000
`iom.wdt.slack`	Slack time (in ms) of the internal timeout handler	4000
`iom.wdt.action`	Execution time (in ms) of the action taken by the watchdog interrupt handler	2000
`iom.wdt.maxInterval`	Maximum timeout interval (in ms) allowed by the watchdog timer API	180000
`iom.wdt.startupInterval`	Maximum time (in ms) required for the startup sequence to complete	0
`iom.wdt.shutdownInterval`	Maximum time (in ms) required for the shutdown sequence to complete	0
`iom.os_gauges.activestart`	OS_GAUGES signaling sysevents actived at C_OS init	0
`iom.os_gauges.syslog`	OS_GAUGES sysevents errors in syslog messages	0
`iom.bootverbose`	C_OS Activate boot verbose mode	0
`iom.nprocs`	C_OS maximum number of processes	64
`iom.nthreadsperproc`	C_OS maximum number of threads per process	64
`iom.nprocsperuid`	C_OS maximum number of processes per user	63
`iom.maxcoresize`	C_OS maximum permitted size of a core file	2100000
`iom.maxsockets`	C_OS maximum number of open sockets	64
`iom.nmbufs`	C_OS maximum number of open sockets	2048
`iom.userstacksize`	Default stack size of user mode threads	0x8000
`cgtp.filter_tab_nb`	CGTP number of filter tables	40
`cgtp.sub_tab_nb`	CGTP number of subtables in filter tables	6
`cgtp.entry_nb`	CGTP number of entries per subtable	[2, 4096] by power of 2
`cgtp.elem_nb`	CGTP number of elements per entry	4
`cgtp.resolution`	Definition of CGTP filter period	4
`iom.ipv6.gif.number`	Number of GIF interfaces	1
`iom.inet.use_hw_checksum`	Mask controlling the use of hardware checksum capability by the networking stack 0x001 -- IP header checksum 0x002 -- TCP header checksum 0x004 -- UDP header checksum 0x008 -- checksum over IP fragments 0x010 -- hardware fragments IP packets 0x100 -- IP header checksum verified on reception 0x200 -- IP header checksum is valid 0x400 -- data checksum computed on reception 0x800 -- data checksum computed with TCP/UDP pseudo headers	0xffff
`iom.rtsig.sigqueuemax`	Maximum number of signals that can be queued per process	32
`sysdump.device`	Device number used to process the TFTP transfer	0

Support for Floating Point Configuration

Version 5.0 of the ChorusOS operating system provides hardware support for floating point configuration. To facilitate this, two new features and one new tunable have been added. The two new features are FPU and FPU_EMUL. The new tunable is kern.exec.dflThreadFpuCtrl.

For the floating point support to be active, set FPU=true and FPU_EMUL=false. Applications should be built with FFPU=ON. With these settings:

A per thread floating point context is allocated.
The microkernel switches a thread's floating point context on demand.

Note -

The sysGetConf(2K) system call has been enhanced to retrieve enabled features. The floating point configuration support applies to the PowerPC platform only.

Support for FPU Exception Handling

A new tunable, kern.exec.dflThreadFpuCtrl, has been added to configure default thread behaviour on floating point exceptions. This tunable is a bit field and is the logical OR of MSR(FE₀,FE₁) bits and FPSCR(24-31) control bits.

The following bits may be set or cleared:

MSR(FE0,FE1)=0x00000000: Floating-point exceptions disabled
MSR(FE0,FE1)=0x00000900: Floating-point precise exception mode
FPSCR(VE)=0x00000080: Invalid operation exception enabled
FPSCR(OE)=0x00000040: Overflow exception enabled
FPSCR(UE)=0x00000020: Underflow exception enabled
FPSCR(ZE)=0x00000010: Zero divide exception enabled
FPSCR(XE)=0x00000008: Inexact operation exception enabled
FPSCR(NI)=0x00000004: Non IEEE mode. This bit should never be set.
FPSCR(RN)=0x00000000: Round to nearest
FPSCR(RN)=0x00000001: Round toward zero
FPSCR(RN)=0x00000002: Round toward +infinity
FPSCR(RN)=0x00000003: Round toward -infinity

MMU/Cache Configuration

To provide MMU/cache configuration , two new tunables have been added:

kern.mem.cacheMode
kern.mem.pgTableSzLog2

kern.mem.cacheMode defines how processor caches should be configured. It is a bit field and is the logical OR of the following bit values:

HID0(ICE)=0x00008000: Instruction cache enabled (L1)
HID0(DCE)=0x00004000: Data cache enabled (L1)
L2CR(L2E)=0x80000000: Unified L2 cache enabled
L2CR(L2DO)=0x00400000: For data access only
L2CR(L2IO)=0x00000400: For instruction access only
L2CR(L2WT)=0x00080000: In write-through mode

kern.mem.pgTableSzLog2 defines the memory size to be allocated to the MMU hardware page table (HTAB). To force the HTAB table size to be a power of 2, the tunable value is defined as Log2(size). Thus, 2^kern.mem.pgTableSzLog2 bytes are allocated to the HTAB table. kern.mem.pgTableSzLog2 must be in the value range [16..25].

Note -

This support applies to the PowerPC platform only.