OS/2, eCS & ArcaOS - Technical > Storage
SATA vs AHCI: why the massive performance difference?
Dariusz Piatkowski:
So I needed to replicate my ThunderBird profile (separate thread on that topic elsewhere) to troubleshoot the Calendar/Google authentication issue and was taken aback by how long it took my backup profile to be copied over.
Did that a couple more times just to see that the results are consistent, and sure enough they are.
Take a look at the attached pics:
1) AHCI configuration (for SDD system) shows a nearly 29mins duration for a 9GB copy
2) SATA (DANIS506) (for the same SDD system) shows a 3 mins duration for the same 9GB copy
This is super strange, and even stranger so given that I do not recall seeing this issue before, albeit I may have updated the AHCI drivers since (haven't tried rolling them back to the previus version and re-testing this).
Is anyone else seeing this kind of an outcome???
System Config
==========
1) PROFILE - 9GB of content, about 5500 files that make up Thunderbird profile.
2) FS - JFS, with 1Gig cache
3) IFS => IFS=G:\OS2\JFS.IFS /CACHE:1048576 /LW:32,128,8 /AUTOCHECK:*
4) CAHEJFS => CALL=G:\OS2\CMD.EXE /Q /C G:\OS2\CACHEJFS.EXE /LW:32,128,8 /MINBUFFER:8000 /MAXBUFFER:24000 >NUL
5) DANIS506 - 1.08.16
6) AHCI - 2.09
7) MSI 990FXA-GD80 => details below
--- Code: ---Bus 0 (PCI Express), Device Number 17, Device Function 0
Vendor 1002h Advanced Micro Devices, Inc. [AMD/ATI]
Device 4390h SB7x0/SB8x0/SB9x0 SATA Controller [IDE mode]
Command 0007h (I/O Access, Memory Access, BusMaster)
Status 0230h (Has Capabilities List, Supports 66MHz, Medium Timing)
Revision 40h, Header Type 00h, Bus Latency Timer 40h
Self test 00h (Self test not supported)
PCI Class Storage, type IDE (ATA)
PCI EIDE Controller Features :
BusMaster EIDE is supported
Primary Channel is in native mode at Addresses 0 & 1
Secondary Channel is in native mode at Addresses 2 & 3
Subsystem ID 76401462h Unknown
Subsystem Vendor 1462h Micro-Star International Co., Ltd. [MSI]
Address 0 is an I/O Port : F090h..F097h
Address 1 is an I/O Port : F080h..F083h
Address 2 is an I/O Port : F070h..F077h
Address 3 is an I/O Port : F060h..F063h
Address 4 is an I/O Port : F050h..F057h
Address 5 is a Memory Address (0-4GiB) : FEB0B000h..FEB0B3FFh
System IRQ 19, INT# A
New Capabilities List Present:
Unknown Capability (Code 12h)!!
Unknown Capability (Code 13h)!!
--- End code ---
Roderick Klein:
Ask Arca Noae, David has done a lot of research and made very good WIKI article how to install ArcaOS under Virtualbox.
https://www.arcanoae.com/wiki/arcaos/installation-planning/virtual-machine-configuration/oracle-vm-virtualbox/
"In Storage, the defaults are fine. Note that an IDE controller is used, and note that the VDI is on IDE Primary Device 0, and the DVD is on IDE Secondary Device 0. This is the recommended configuration as the DVD should not be on the same controller (Primary vs Secondary) as the VDI. Add additional controllers and disks as necessary. The IDE controller is the fastest emulation. Other devices such as AHCI will work also but the emulation is slower."
It contains more usefull tips how to get the best performance out of Virtualbox.
Roderick
Lars:
add /N /F switches to OS2AHCI.ADD. I understood that in particular when using JFS the /F switch will improve performance as it ignores any write-through setting of the FS in order to prevent lengthy disk operations.
Dariusz Piatkowski:
Hello Lars,
--- Quote from: Lars on August 09, 2026, 10:56:28 pm ---add /N /F switches to OS2AHCI.ADD. I understood that in particular when using JFS the /F switch will improve performance as it ignores any write-through setting of the FS in order to prevent lengthy disk operations.
--- End quote ---
I'm on AHCI v2.09 (Jun_2023) which claims to do '/N' by default...however, I will give the '/F' option a go and see if that makes a difference.
Thank you!
Dariusz Piatkowski:
Hello Roderick,
--- Quote from: Roderick Klein on August 09, 2026, 04:51:44 pm ---Ask Arca Noae, David has done a lot of research and made very good WIKI article how to install ArcaOS under Virtualbox....
--- End quote ---
I'm running on real hardware here, and in my case the MSI 990FXA-GD80 motherboard has two SATA controllers:
1) JMicron
- nothing is hooked up to this
2) ATI SB850 chipset
- everything is hooked up to this (when the BIOS is configured for AHCI mode)
As best as I can tell my motherboard does not support having software (driver) selectable SATA vs AHCI device mode, you set it to either one at BIOS level.
Navigation
[0] Message Index
[#] Next page
Go to full version