FreeBSD 5.3b7and poor ata performance

[fandino]

Kenneth Culver wrote:

>> # dd if=/dev/stripe/test of=/dev/null bs=1024k count=1024
>> 1073741824 bytes transferred in 30.072215 secs (35705445 bytes/sec)
>>
>> simply it doesn't makes any sense. With two disk I'd must have
>> approx. 26K+26K=52 M/sec and with four 26K+26K+26K+26K=104 M/sec
>>
>> Other systems like OpenBSD had a good throughput 55000K/sec by disk

> ar0: 228880MB <ATA RAID0 array> [29178/255/63] status: READY subdisks:
>  disk0 READY on ad4 at ata2-master
>  disk1 READY on ad6 at ata3-master
> 
> I get the following performance with dd:
> 
> dd if=/dev/ad4 of=/dev/null bs=1m count=200
> 209715200 bytes transferred in 3.538456 secs (59267433 bytes/sec)
> 
> dd if=/dev/ad6 of=/dev/null bs=1m count=200
> 209715200 bytes transferred in 3.551439 secs (59050767 bytes/sec)
> 
> dd if=/dev/ar0 of=/dev/null bs=1m count=200

> 209715200 bytes transferred in 1.837508 secs (114130226 bytes/sec)
> 
> This is with a custom kernel with all debugging options off. I haven't seen a
> mail from you yet that says whether you turned off debugging options in the
> kernel or not, and if you haven't turned off debugging options, I'd strongly
> suggest doing so.

with my custom and stripped kernel (I attach it below) I don't see any difference.

# dd if=/dev/ad4 of=/dev/null bs=1024k count=1024
1024+0 records in
1024+0 records out
1073741824 bytes transferred in 30.606110 secs (35082597 bytes/sec)

# grep '^[^#]' /usr/src/sys/i386/conf/GENERIC
cpu		I686_CPU
ident		GENERIC
options 	SCHED_4BSD		# 4BSD scheduler
options 	INET			# InterNETworking
options 	INET6			# IPv6 communications protocols
options 	FFS			# Berkeley Fast Filesystem
options 	SOFTUPDATES		# Enable FFS soft updates support
options 	UFS_ACL			# Support for access control lists
options 	UFS_DIRHASH		# Improve performance on big directories
options 	MD_ROOT			# MD is a potential root device
options 	NFSCLIENT		# Network Filesystem Client
options 	NFSSERVER		# Network Filesystem Server
options 	NFS_ROOT		# NFS usable as /, requires NFSCLIENT
options 	MSDOSFS			# MSDOS Filesystem
options 	CD9660			# ISO 9660 Filesystem
options 	PROCFS			# Process filesystem (requires PSEUDOFS)
options 	PSEUDOFS		# Pseudo-filesystem framework
options 	GEOM_GPT		# GUID Partition Tables.
options 	COMPAT_43		# Compatible with BSD 4.3 [KEEP THIS!]
options 	COMPAT_FREEBSD4		# Compatible with FreeBSD4
options 	SCSI_DELAY=15000	# Delay (in ms) before probing SCSI
options 	KTRACE			# ktrace(1) support
options 	SYSVSHM			# SYSV-style shared memory
options 	SYSVMSG			# SYSV-style message queues
options 	SYSVSEM			# SYSV-style semaphores
options 	_KPOSIX_PRIORITY_SCHEDULING # POSIX P1003_1B real-time extensions
options 	KBD_INSTALL_CDEV	# install a CDEV entry in /dev
options 	AHC_REG_PRETTY_PRINT	# Print register bitfields in debug
					# output.  Adds ~128k to driver.
options 	AHD_REG_PRETTY_PRINT	# Print register bitfields in debug
					# output.  Adds ~215k to driver.
options 	ADAPTIVE_GIANT		# Giant mutex is adaptive.
device		isa
device		pci
device		fdc
device		ata
device		atadisk		# ATA disk drives
device		ataraid		# ATA RAID drives
device		atapicd		# ATAPI CDROM drives
device		atapifd		# ATAPI floppy drives
device		atapist		# ATAPI tape drives
options 	ATA_STATIC_ID	# Static device numbering
device		atkbdc		# AT keyboard controller
device		atkbd		# AT keyboard
device		psm		# PS/2 mouse
device		vga		# VGA video card driver
device		splash		# Splash screen and screen saver support
device		sc
device		agp		# support several AGP chipsets
device		npx
device		pmtimer
device		sio		# 8250, 16[45]50 based serial ports
device		ppc
device		ppbus		# Parallel port bus (required)
device		lpt		# Printer
device		plip		# TCP/IP over parallel
device		ppi		# Parallel port interface device
device		miibus		# MII bus support
device		re		# RealTek 8139C+/8169/8169S/8110S
device		rl		# RealTek 8129/8139
device		loop		# Network loopback
device		mem		# Memory and kernel memory devices
device		io		# I/O device
device		random		# Entropy device
device		ether		# Ethernet support
device		sl		# Kernel SLIP
device		ppp		# Kernel PPP
device		tun		# Packet tunnel.
device		pty		# Pseudo-ttys (telnet etc)
device		md		# Memory "disks"
device		gif		# IPv6 and IPv4 tunneling
device		faith		# IPv6-to-IPv4 relaying (translation)
device		bpf		# Berkeley packet filter