PS2 Max theoretically and practical PS2 transfer speed with OPL

jolek

Senior Member
Due to some optimization made recently OPL BETAs should be at least faster than old OPL 0.9.3 through USB.
What is the current transfer speed for all of these devices (HDD, ETH, USB)?

Maximum theoretically speed for almost all devices in PS2 is:
  • HDD ATA interface: ATA-66 (Roughly 66MB/s).
  • Ethernet interface: 100Mbit (Or 12.5MB/s).
  • USB 1.1 interface: 12Mbit (~1.5 MB/s).
  • CD/DVD drive: 24x speed CD-ROM [3.6 MB/s], 4x speed DVD-ROM [5.28 MB/s].
 
Those numbers are very optimistic. Other than overhead stemming from the software-level protocols involved, we're also constrained by hardware limitations. So such numbers cannot be reached when the interface is used in practical applications.

For Ethernet, I got 8.6MB/s over TCP, when the TCP/IP stack is put on the EE. However, that is with no additional load. In HDLGameInstaller, you can see that people have gotten up to 7.7MB/s. The additional overhead likely comes from supporting other devices and writing data to the HDD.
With the IOP alone, we might get about 3MB/s (you can refer to HDLDump's speeds). At some point, I released a mod of HDLDump v0.9.1 that allowed up to 5.8MB/s with the IOP alone, but that was with the UDP server (we don't usually use UDP for transferring data).

For USB, Maximus32 got slightly over 1MB/s.
 
Those numbers are very optimistic. Other than overhead stemming from the software-level protocols involved, we're also constrained by hardware limitations. So such numbers cannot be reached when the interface is used in practical applications.

That is why I added theoretically. ;)

For Ethernet, I got 8.6MB/s over TCP, when the TCP/IP stack is put on the EE. However, that is with no additional load. In HDLGameInstaller, you can see that people have gotten up to 7.7MB/s. The additional overhead likely comes from supporting other devices and writing data to the HDD.
With the IOP alone, we might get about 3MB/s (you can refer to HDLDump's speeds). At some point, I released a mod of HDLDump v0.9.1 that allowed up to 5.8MB/s with the IOP alone, but that was with the UDP server (we don't usually use UDP for transferring data).

zastanawia.gif

Let me get this clear.
Due the hardware limitation, max theoretically speed through ETH is 8.6MB/s.
Practical transfer speed while transferring game with HDLGameInstaller it can be up to 7.7MB/s

What about OPL? Can we currently get above 2MB/s (e.g. 2.5-3 MB/s)?
I mean what max transfer speed we can get from e.g. OPL 1220.

For USB, Maximus32 got slightly over 1MB/s.

It was some kind of a debug test?
I mean testing max transfer speed with some kind of a dedicated test?
Or even currently OPL should be able to reach 1MB/s e.g. while watching FMV?
 
What about OPL? Can we currently get above 2MB/s (e.g. 2.5-3 MB/s)?
I mean what max transfer speed we can get from e.g. OPL 1220.

That, I do not know for sure because I last measured SMB's mediocre performance before I backported the TCPIP core locking feature from a new version of LWIP. We might be getting something about 3MB/s, which would explain the much smoother experience today. But it will not be exceptional.

It was some kind of a debug test?
I mean testing max transfer speed with some kind of a dedicated test?

His speed tests involved reading and writing sectors of varying lengths. The best it can go under ideal conditions was slightly over 1MB/s.
With a filesystem, it will be slower because of a need to query the filesystem for the clusters in use, but here we ignore the filesystem and assume that the file(s) are in single pieces.

Or even currently OPL should be able to reach 1MB/s e.g. while watching FMV?

This is a possibility, since we ignore the filesystem. As long as the game makes longer reads, it will likely reach 1MB/s.
Smaller reads will result in very poor performance.

What about HDLoader U5 (100mbps) and U6 (133,3mbps)??
The PlayStation 2 only supports up to UDMA mode 4, as it was originally designed to be compliant with ATA-4. There is no datasheet for the SPEED's ATA controller, so we do not know how to make it support UDMA modes 5 & 6, if it even can.
 
Here's a benchmark program for r/w speed: https://github.com/rickgaiser/ps2-rw-speed
Edit ee/config.h to your needs.

There has been some progress in a network protocol that is faster and smaller than SMB, but it currently doesn't work yet: https://github.com/rickgaiser/Open-PS2-Loader (look in bdm branch)

Once that is finished, compatibility and speed should increase.

It would be nice to debug the issue...

The expansion port, the PCMCIA slot, and the IEEE1394 port are the fastest ways to get data to the PS2. All of those will saturate the IOP's bandwidth.
 
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What's the other way around? Is there a possibility (software-side) to adjust the HDD speed to USB/DVD speed without damaging the read head?

If you play games like Mortal Kombat Deception or Armageddon (online), the connection will fail if the people don't use the same storage. I know it's not a big priority but I'm curious :-)
 
You mean that game works through USB/DVD, but have a problem with HDD,
so you suggest to lower transfer speed?
 
Forget what I wrote...

I now tried that with 2 consoles (one goes online with USB and the latest OPL and the other with DVD) and it really works. No online connection errors. I am very surprised :-)

... but yes, the HDD is always too fast. Reducing the HDD speed to a 4x DVD speed for online game compatibility should work, like what MODE 1 should do (if I get that right) but it does nothing on my side.

Older ATA-PIO modes like PIO 1 are nearly at 4x DVD speed. Are they not compatible on the PS2?
 
Forget what I wrote...

I now tried that with 2 consoles (one goes online with USB and the latest OPL and the other with DVD) and it really works. No online connection errors. I am very surprised :)

... but yes, the HDD is always too fast. Reducing the HDD speed to a 4x DVD speed for online game compatibility should work, like what MODE 1 should do (if I get that right) but it does nothing on my side.

Older ATA-PIO modes like PIO 1 are nearly at 4x DVD speed. Are they not compatible on the PS2?
by Kermit ODEM DBGCORE v0.4 BETA,you can use PIO modes
 
Forget what I wrote...

I now tried that with 2 consoles (one goes online with USB and the latest OPL and the other with DVD) and it really works. No online connection errors. I am very surprised :)

... but yes, the HDD is always too fast. Reducing the HDD speed to a 4x DVD speed for online game compatibility should work, like what MODE 1 should do (if I get that right) but it does nothing on my side.

Older ATA-PIO modes like PIO 1 are nearly at 4x DVD speed. Are they not compatible on the PS2?

Mode 1 should also reduce reading speed into 3600 KB/s:
https://github.com/ifcaro/Open-PS2-Loader/commit/479f83b7bfb9bf08362c792920446f2800af7aa9.

Max PS2 transfer speed for:
CD-ROM is 24x speed [3.6 MB/s],
DVD-ROM is 4x speed [5.28 MB/s].
https://en.wikipedia.org/wiki/PlayStation_2_technical_specifications#Optical_disc_drive.
 
Mode 1 should also reduce reading speed into 3600 KB/s:
https://github.com/ifcaro/Open-PS2-Loader/commit/479f83b7bfb9bf08362c792920446f2800af7aa9.

Max PS2 transfer speed for:
CD-ROM is 24x speed [3.6 MB/s],
DVD-ROM is 4x speed [5.28 MB/s].
https://en.wikipedia.org/wiki/PlayStation_2_technical_specifications#Optical_disc_drive.

Thanks for the links. I'll check that again and post my issues on the associated thread. I know it's about the theoretically/practical speed here and not about bug reports :-)
 
I've been trying recently Conflict - Global Storm (SLES_525.73) through SMB on SCPH-77004 & SCPH-50004
with various OPL version (1086, 1196, 1357).
On SCPH-77004 everything is smooth (intro FMV & main menu), while on SCPH-50004 there is noticeable stuttering.
Through HDD on SCPH-50004 everything was fine.

From I remember USB transfer on SLIM models is faster, does it also applies for SMB?
 
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Has anyone ever got more than 1.8 or 2.4MB/s from disc?

I suppose a speed based on the sector(number) and some real life-speed-tests on/of CDs/DVDs might be a way to yield these 'ultra-correct' read-speeds, but it would probably still be quite dependent on other things like threading and used device...
 
Has anyone ever got more than 1.8 or 2.4MB/s from disc?

Using HDLGameInstaller I'm getting 2875 KB/s from DVD:
25052018421.png

Unfortunately I do not remember what was that (max) speed for CD.

BTW I've recently got SCPH-70004 & 75004 models.
FMV stutters more on SCPH-70004 than 75004 through USB.
I mean that faster USB transfer speed became noticeable from SCPH-7500X models.
So not all SLIM models through USB (probably also SMB) are faster that FAT.
 
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I meant directly on a PS2, i.e. when using disc-test-tools or simply by dumping a game via HDL...
 
I meant directly on a PS2, i.e. when using disc-test-tools or simply by dumping a game via HDL...

That image in my previous post was from installing game through HDLGameInstaller into PS2HDD,
so now I'm confused?!
I launched "HDLGameInstaller.elf" on PS2 via wLe, inserted PS2 disk and I started installing a game.
 
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Using HDLGameInstaller I'm getting 2875 KB/s from DVD:]
The speeds increase as the data is further to the edge of the disc. As you have taken the picture at the very beginning of the installation you have gotten basically the worst case scenario. On my dying laser at the beginning I get ~2300 kB/s, while at the end of a 4 GB+ game it's ~3200 kB/s
 
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