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Finally found a use for a ram disk

You've given me an idea…

EDIT: Yep. Put the app and my profile folder on the ram disk.

Loads super fast.

To preserve things I've added my ram disk to Time Machine's backup.
 
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Anyone remember the Amiga, where a RAM disk is always auto-mounted :)

Amiga.jpg
 
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Picture 2.png

Photoshop CS3 has a RAM limit of 3GB despite my G5 having 16GB of RAM. By adding the 2GB RamDisk as the first drive in the scratch disk stack, I can effectively increase Photoshop's allowance to 5GB.

Is this any different in CS4? I skipped a few versions and upgraded from CS3 (Universal) to CS6 (Intel).
[doublepost=1508500361][/doublepost]
MysticCow said:
TFF on a RAM disk. Now I have to try this.
Click to expand...

It's snappy!
  • TFF launch time is bang on 4 mississippis from double-click to an active, ready TFF search box.
  • LWK launches in under 2 seconds, with a ready and waiting Google search box. This launch time is perfectly on par with Safari 11 under High Sierra on my iMac (Late 2009) with an mSATA SSD.
  • Doom 3 (1.5GB) load times are substantially faster. Not quite light-speed, but the Mac port of the game has always suffered from long load times. I'd say it's on par with the Windows version like this.
What other disk heavy apps and games would benefit from this?
 
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amagichnich said:
I always assumed PS uses the scratch disk when ram is full - am I wrong and have to rethink my PS environment?
Click to expand...
I don't know how that works. But as a disk, you can specify that ram as scratch in PS because it's being seen as a disk.
 
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Played with this again a bit yesterday. It would appear that the 2GB limit for Leopard stands.

Found an older post where a member had released Ram Disk Creator which is quite useful for creating multiple RAM disks.

The problem is that the only solution to a larger than 2GB disk is to RAID them. And the problem with that is that unless you eject the RAID from Disk Utility (verus the Finder) the disks will continue to occupy ram.

So, it would seem that Esperance is still the best solution for ONE ram disk while you can use RDC to create multiple disks if you like.
 
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eyoungren said:
Played with this again a bit yesterday. It would appear that the 2GB limit for Leopard stands.

Found an older post where a member had released Ram Disk Creator which is quite useful for creating multiple RAM disks.

The problem is that the only solution to a larger than 2GB disk is to RAID them. And the problem with that is that unless you eject the RAID from Disk Utility (verus the Finder) the disks will continue to occupy ram.

So, it would seem that Esperance is still the best solution for ONE ram disk while you can use RDC to create multiple disks if you like.
Click to expand...

The 2GB limit is due to how a 32-bit binary handles memory. A single process cannot address more than 2048MB

I guess the question comes down to; When would you realistically need more than 2GB on a temporary RAM disk?

With a 16GB G5, you could easily allocate 8 or even 12GB to RAM disks and never find the Mac paging due to low memory. In a world where an 8GB System is now considered lightweight, it’s easy to forget that even 2GB was ample for Leopard to fly while running multiple apps.

In regards to other options, there are a series of Terminal commands to achieve the RAM disk creation across multiple versions of Mac OS X. This includes Tiger and also more recent El Cap and presumably Sierra/High Sierra.

http://osxdaily.com/2007/03/23/create-a-ram-disk-in-mac-os-x/

One could write a short shell script to create these RAM disks and also create the soft RAID, then add it to the User Account Login Items to init on startup.

The script could also copy regular use apps across.

For someone who relies on QEMU under OS X (@Lastic) or VirtualPC to emulate a system, copying the entire VM across to the RAMdisk should make for a substantial increase in performance.
 
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eyoungren said:
Played with this again a bit yesterday. It would appear that the 2GB limit for Leopard stands.

Found an older post where a member had released Ram Disk Creator which is quite useful for creating multiple RAM disks.

The problem is that the only solution to a larger than 2GB disk is to RAID them. And the problem with that is that unless you eject the RAID from Disk Utility (verus the Finder) the disks will continue to occupy ram.

So, it would seem that Esperance is still the best solution for ONE ram disk while you can use RDC to create multiple disks if you like.
Click to expand...
hi
i tried to move the firefox cache to another partition but it did not work
how can move the firefox cache to another partion?
i'm a novice , at browser.cache.disk.parent_directory what should i write??
how can i find the volume/partion name ?
can you do an example?
thanks
[doublepost=1508781824][/doublepost]
Dronecatcher said:
Anyone remember the Amiga, where a RAM disk is always auto-mounted :)

View attachment 726323
Click to expand...
mythical amiga !
 
supergaia said:
hi
i tried to move the firefox cache to another partition but it did not work
how can move the firefox cache to another partion?
i'm a novice , at browser.cache.disk.parent_directory what should i write??
how can i find the volume/partion name ?
can you do an example?
thanks
[doublepost=1508781824][/doublepost]
mythical amiga !
Click to expand...
browser.cache.disk.parent_directory is the string value

The value for browser.cache.disk.parent_directory is /Volumes/YV14_RAM_2G/

…on my system.

Where: /Volumes/YV14_RAM_2G/ is you will need to put in your own path to your ram disk.
 
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eyoungren said:
browser.cache.disk.parent_directory is the string value

The value for browser.cache.disk.parent_directory is /Volumes/YV14_RAM_2G/

…on my system.

Where: /Volumes/YV14_RAM_2G/ is you will need to put in your own path to your ram disk.
Click to expand...
hi
thanks!
have you tried another ram disk programs?
thanks again for firefox ,even i'm a chrome user :(
appreciate it , cheers
 
AphoticD said:
The 2GB limit is due to how a 32-bit binary handles memory. A single process cannot address more than 2048MB

I guess the question comes down to; When would you realistically need more than 2GB on a temporary RAM disk?

With a 16GB G5, you could easily allocate 8 or even 12GB to RAM disks and never find the Mac paging due to low memory. In a world where an 8GB System is now considered lightweight, it’s easy to forget that even 2GB was ample for Leopard to fly while running multiple apps.

In regards to other options, there are a series of Terminal commands to achieve the RAM disk creation across multiple versions of Mac OS X. This includes Tiger and also more recent El Cap and presumably Sierra/High Sierra.

http://osxdaily.com/2007/03/23/create-a-ram-disk-in-mac-os-x/

One could write a short shell script to create these RAM disks and also create the soft RAID, then add it to the User Account Login Items to init on startup.

The script could also copy regular use apps across.

For someone who relies on QEMU under OS X (@Lastic) or VirtualPC to emulate a system, copying the entire VM across to the RAMdisk should make for a substantial increase in performance.
Click to expand...

So I took the plunge before the paycheck came in and bought used 4 x 2GB RAM to bring my total RAM to 12 GB now.

First thing copy a 3,7 GB Win 7 qemu image to a 2 x 2 GB RAID RAMdisk.
Booting Win 7 x86 still takes up to 6 minutes to get to a desktop but once it's running it is more snappy , the problem is that CPU load on the 1 core VM, qemu does spread over my G5's dual cores, must check again with a different machine type or more virtual cores.

Doing the same with my Debian i386 qemu image ( no WM just text console ) , boot times are identical from RAMdisk or SSD.

Will try with a Win FLP or XP Lite image also maybe Ubuntu Mate , currently just feels like increase in snappyness but not boot times.

All this whilst typing this and thus running TFF (not from RAMdisk yet).
 
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Lastic said:
So I took the plunge before the paycheck came in and bought used 4 x 2GB RAM to bring my total RAM to 12 GB now.

First thing copy a 3,7 GB Win 7 qemu image to a 2 x 2 GB RAID RAMdisk.
Booting Win 7 x86 still takes up to 6 minutes to get to a desktop but once it's running it is more snappy , the problem is that CPU load on the 1 core VM, qemu does spread over my G5's dual cores, must check again with a different machine type or more virtual cores.

Doing the same with my Debian i386 qemu image ( no WM just text console ) , boot times are identical from RAMdisk or SSD.

Will try with a Win FLP or XP Lite image also maybe Ubuntu Mate , currently just feels like increase in snappyness but not boot times.

All this whilst typing this and thus running TFF (not from RAMdisk yet).
Click to expand...

Can you assign 2 cpus to the x86 vms in OS X QEMU? I found the best VM results on my G5 to be under Linux with KVM enabled using the ppc64 power series machine type. I can assign 2 cpus (on the DC). It honestly performs as well as VMWare Fusion does on an x86_64. Boot times and compiling almost feel "native".

This is impressive considering the G5 wasn't designed with any kind of hypervisor support in mind.

EDIT: This gives me an idea... I wonder if I could create a RAM disk in Linux and put the vms on there. Using KVM, it should in theory, fly like a rocket.
 
AphoticD said:
Can you assign 2 cpus to the x86 vms in OS X QEMU? I found the best VM results on my G5 to be under Linux with KVM enabled using the ppc64 power series machine type. I can assign 2 cpus (on the DC). It honestly performs as well as VMWare Fusion does on an x86_64. Boot times and compiling almost feel "native".

This is impressive considering the G5 wasn't designed with any kind of hypervisor support in mind.

EDIT: This gives me an idea... I wonder if I could create a RAM disk in Linux and put the vms on there. Using KVM, it should in theory, fly like a rocket.
Click to expand...

Did I understand correctly that your running qemu-kvm on Linux PPC on a G5 and then launching ppc64 VM's ?

Will have to check smp or machine types under qemu 2.2.0 OS X 10.5.8, coming from running qemu on a PB G4 still have a lot to play around with qemu now on the G5 but the herd is ready on my day off

IMG_3341.JPG

IMG_3342.JPG
 
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Lastic said:
Did I understand correctly that your running qemu-kvm on Linux PPC on a G5 and then launching ppc64 VM's ?

Will have to check smp or machine types under qemu 2.2.0 OS X 10.5.8, coming from running qemu on a PB G4 still have a lot to play around with qemu now on the G5 but the herd is ready on my day off

View attachment 727422
View attachment 727423
Click to expand...

The server HQ is looking mighty!

Yes, I've got Ubuntu Mate PPC 16.04 installed with the latest QEMU 2.10 compiled from official source (no patches). Then running two separate 2xCPU VMs under qemu-system-ppc64 -M pseries with max RAM of 1792MB each.

Currently I have Debian 8 Jessie (ppc64) and Fedora Server 25 (ppc64). Installation for both required no special tricks. Just launch the VMs from the ppc ISOs and install.

I haven't run the Fedora 26 update on the VM yet, but should check that out.

If you haven't tried it already, I would definitely recommend installing Fedora server and utilize the cockpit web front-end. It's very slick. You just need to forget about apt and use dnf for package management.
 
AphoticD said:
The server HQ is looking mighty!

Yes, I've got Ubuntu Mate PPC 16.04 installed with the latest QEMU 2.10 compiled from official source (no patches). Then running two separate 2xCPU VMs under qemu-system-ppc64 -M pseries with max RAM of 1792MB each.

Currently I have Debian 8 Jessie (ppc64) and Fedora Server 25 (ppc64). Installation for both required no special tricks. Just launch the VMs from the ppc ISOs and install.

I haven't run the Fedora 26 update on the VM yet, but should check that out.

If you haven't tried it already, I would definitely recommend installing Fedora server and utilize the cockpit web front-end. It's very slick. You just need to forget about apt and use dnf for package management.
Click to expand...

Might be tempted to try Ubuntu Mate again on the G5 , did try to run Fedora ppc64 natively like the Amiga guys do

https://forums.macrumors.com/threads/wip-fedora-25-server-on-powermac-g5.2054552/

, Fedora is indeed nice , using Workstation 26 on my x86 Lenovo, also read somewhere that Centos would install on Xserve G4, so many tinkering options :)
 
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Lastic said:
Might be tempted to try Ubuntu Mate again on the G5 , did try to run Fedora ppc64 natively like the Amiga guys do

https://forums.macrumors.com/threads/wip-fedora-25-server-on-powermac-g5.2054552/

, Fedora is indeed nice , using Workstation 26 on my x86 Lenovo, also read somewhere that Centos would install on Xserve G4, so many tinkering options :)
Click to expand...

And so many late nights ahead of you!

I can't count how many times I've met with a client or gone into work and had "Dude. You always look so tired." ... (Thanks, I feel it too.)

Such is the life of the technology addict. There is just too much to learn and I still feel like I don't know jack.
[doublepost=1509005822][/doublepost]
kvmPPC64-screenshot.png


Here you can see the VM overhead on the CPU Blowfish test indicates a loss of about 10%. This is with the three systems running simultaneously (host + 2 guests).

EDIT: Upon closer inspection, it appears my logic is backward. The blowfish test shows the CPU performs ~10% FASTER in the VM than natively! That is strange.
 
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AphoticD said:
And so many late nights ahead of you!

I can't count how many times I've met with a client or gone into work and had "Dude. You always look so tired." ... (Thanks, I feel it too.)

Such is the life of the technology addict. There is just too much to learn and I still feel like I don't know jack.
[doublepost=1509005822][/doublepost]View attachment 727427

Here you can see the VM overhead on the CPU Blowfish test indicates a loss of about 10%. This is with the three systems running simultaneously (host + 2 guests).

EDIT: Upon closer inspection, it appears my logic is backward. The blowfish test shows the CPU performs ~10% FASTER in the VM than natively! That is strange.
Click to expand...

So which version of qemu do you have on Ubuntu Mate 16.4 ?
How much RAM maximum can you assign your ppc64 VM's ?
 
Lastic said:
So which version of qemu do you have on Ubuntu Mate 16.4 ?
How much RAM maximum can you assign your ppc64 VM's ?
Click to expand...

apt will install qemu 2.5.0 with a multitude of stability patches for ppc, but I found that 2.10 builds and compiles easily.

Download the current source (2.10.1) from qemu.org. Here's a dump of my build commands from .bash_history:
Code: 
tar Jxpvf qemu-2.10.1.tar.xz
cd qemu-2.10.1/
mkdir build
cd build
../configure --target-list=ppc64-softmmu,ppc-softmmu --enable-vnc-jpeg --audio-drv-list=alsa
make -j8
make install

You could also add i386-softmmu,x86_64-softmmu for emulation support. KVM for ppc and ppc64 is enabled by default.

Run with something like:
Code: 
kvm -m 1792 -drive file=debimage,format=raw -usbdevice tablet -smp cpus=2 -vga std -g 1280x800x32 -cdrom debian-powerpc-netinst.iso -boot d

(kvm is by default, a symlink to qemu-system-ppc64 on this platform with the default machine type being pseries)

I found you can assign a maximum of 1792MB (7x256) per vm. 2048 results in an error and 2047 is not divisible by 256.
 
Dronecatcher said:
Anyone remember the Amiga, where a RAM disk is always auto-mounted :)
Click to expand...


Sure do (and use it daily till today).

Good things bout RAM disk in Amiga/MorphOS:

- dynamic size
- place where the system and apps store their current settings (hence you get the "Use" option in prefs)
- optimal place to (initial) store downloads without cluttering your HD with c##p
 
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Can you allocate RAM disk to OS itself so that it boots faster?

P. S. I know I need to get an SSD, but that’s in plans so far.
 
barracuda156 said:
Can you allocate RAM disk to OS itself so that it boots faster?
Click to expand...
On an Amiga, yes. On a Mac, for OS X — not to my knowledge.

If you really want a bootable “RAM disk” that behaves like a hard drive... Acard ANS-9010. ;) That's from a time when “good” SSDs had not yet become affordable though. Not worth bothering with these days.
 
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