Expand VM
Hi all
I have one idea , and this is about expand virtual memory on linux boxes connected in LAN.
Example: Linux A is processing come information , and need more memory , so with this source , Linux A could access virtual memory on Linux B in LAN. But i don´t know how translate the virtual address between Linux A and B , to have success in acess VM, or how to send all the process for Linux B to be processed.
Any ideas ?
Thanks
Breno
----------------------
WebMail Bandnet.com.br
Quoted 11 lines · User &
Hi all
I have one idea , and this is about expand virtual memory on linux boxes connected in LAN.
Example: Linux A is processing come information , and need more memory , so with this source , Linux A could access virtual memory on Linux B in LAN. But i don´t know how translate the virtual address between Linux A and B , to have success in acess VM, or how to send all the process for Linux B to be processed.
Quoted 4 lines
Any ideas ?
Thanks
Breno
Use a swap-file on another machine on the LAN to extend your virtual memory if you run out of local swap-file space.
Cheers,
Dick Johnson
Penguin : Linux version 2.4.18 on an i686 machine (797.90 BogoMips). Why is the government concerned about the lunatic fringe? Think about it.
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Use a swap-file on another machine on the LAN to extend your virtual memory if you run out of local swap-file space.
What would be really good would be a multiple gigabyte solid state 'disk', on a shared SCSI bus...
John.
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Use a swap-file on another machine on the LAN to extend your virtual memory if you run out of local swap-file space.
What would be really good would be a multiple gigabyte solid state 'disk', on a shared SCSI bus...
If you can afford gigabytes of solid state memory, you can surely afford to properly fit your boxes out in the first place.
Signature · 4 lines
/ | [|] Sean Neakums | Size *does* matter. [|] <[email protected]> | That's why I use Emacs. \ |
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Use a swap-file on another machine on the LAN to extend your virtual memory if you run out of local swap-file space.
What would be really good would be a multiple gigabyte solid state 'disk', on a shared SCSI bus...
If you can afford gigabytes of solid state memory, you can surely afford to properly fit your boxes out in the first place.
Good point :-)
What I'd really like to see is a single device which appears as two logical IDE or SCSI devices, one of which has 512 Mb of battery backed RAM, and the other one 512 Mb of EEPROM.
No need for expensive flash memory, just cheap DRAM, and a few NiMH cells to keep the RAM contents intact when the main power was disconnected.
I've seen loads of solid state devices based on flash memory, but few that are based on battery backed DRAM :-(.
John.
There is a good reason for that: Power consumption.
A large SDRAM disk would require refresh logic etc. So you will end up with something closely resembling bad notebook PC.
Quoted 4 lines · John Bradford
I've seen loads of solid state devices based on flash memory, but few that are based on battery backed DRAM :-(.
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I've seen loads of solid state devices based on flash memory, but few that are based on battery backed DRAM :-(.
There is a good reason for that: Power consumption.
A large SDRAM disk would require refresh logic etc. So you will end up with something closely resembling bad notebook PC.
I suppose it makes sense for portable devices, but would it really be that bad for desktop/server use? I was only thinking of about a 24 hour battery backup time - to keep the contents overnight, for example.
John.
The trouble is that you will spend so much money on the power supply, that the product won't make economic sense. It would be better to just use a general purpose PC mother board, PSU and a UPS, since then, you get tremendous economy of scale.
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I've seen loads of solid state devices based on flash memory, but few that are based on battery backed DRAM :-(.
There is a good reason for that: Power consumption.
A large SDRAM disk would require refresh logic etc. So you will end up with something closely resembling bad notebook PC.
I suppose it makes sense for portable devices, but would it really be that bad for desktop/server use? I was only thinking of about a 24 hour battery backup time - to keep the contents overnight, for example.
John.
Quoted 4 lines · User &
I have one idea , and this is about expand virtual memory on linux boxes connected in LAN.
Example: Linux A is processing come information , and need more memory , so with this source , Linux A could access virtual memory on Linux B in LAN.
We've seen *this* done before (remember diskless Sun3-50's?) - the /dev/swap file would be a large file on an NFS mount from a server. At the time, this actually made performance sense, because the old 'Shoebox' drives the -50 came with were incredibly slow, and you could actually do an NFS operation to a larger server (a -280 with Fujitsu SuperEagle disks, for instance) faster than talking to the local disk.
These days, it's probably easier and cheaper to just buy more RAM and/or disk for Linux A.
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But i don´t know how translate the virtual address between Linux A and B , to have success in acess VM, or how to send all the process for Linux B to be processed.
Sending the whole process to Linux B to be processed is called "process migration", and is a difficult problem. Moving the memory image of the process is usually pretty easy. What is difficult is moving things like references to open files, file locks, and so on (what if the process is actively writing to block 739 of /usr/foo/some.file, and the LinuxB machine doesn't have a /usr/foo, or the permissions on some.file don't match, or another process has it locked, or... ) There be nasty dragons in this.
You're probably better off buying more RAM and disk for your A machine.
Signature · 3 lines
Valdis Kletnieks Computer Systems Senior Engineer Virginia Tech
Hi Valdis
Create a new VMA on Linux B for Linux A is easy , but i have a problem , the address of VMA is returned on Linux B , so the VMA created on Linux B can not be used for process of linux A.
The problem is "how can i return address of VMA created on LINUX B to Linux A , and use this space ?".
Thanks
Breno
On Thu, 23 Jan 2003 11:55:38 -0500, Valdis.Kletnieks wrote
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Quoted 3 lines · User &
I have one idea , and this is about expand virtual memory on linux boxes connected in LAN.
Example: Linux A is processing come information , and need more memory ,
so
Quoted 10 lines
Quoted 1 line
with this source , Linux A could access virtual memory on Linux B in LAN.
We've seen *this* done before (remember diskless Sun3-50's?) - the
/dev/swapfile would be a large file on an NFS mount from a server. At the time, this actually made performance sense, because the old 'Shoebox' drives the -50 came with were incredibly slow, and you could actually do an NFS operation to a larger server (a -280 with Fujitsu SuperEagle disks, for instance) faster than talking to the local disk.
Quoted 4 lines
These days, it's probably easier and cheaper to just buy more RAM and/or disk for Linux A.
Quoted 1 line
But i don´t know how translate the virtual address between Linux A and
B , to
Quoted 1 line
Quoted 1 line
have success in acess VM, or how to send all the process for Linux B to
be
Quoted 11 lines
Quoted 1 line
processed.
Sending the whole process to Linux B to be processed is called "process migration", and is a difficult problem. Moving the memory image of the process is usually pretty easy. What is difficult is moving things like references to open files, file locks, and so on (what if the process is actively writing to block 739 of
/usr/foo/some.file, and the LinuxB machine doesn't have a/usr/foo, or the permissions on some.file don't match, or another process has it locked, or... ) There be nasty dragons in this.
Quoted 5 lines
You're probably better off buying more RAM and disk for your A machine.
Signature · 3 lines
Valdis Kletnieks Computer Systems Senior Engineer Virginia Tech
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WebMail Bandnet.com.br
Quoted 4 lines · User &
Create a new VMA on Linux B for Linux A is easy , but i have a problem , the address of VMA is returned on Linux B , so the VMA created on Linux B can not
be used for process of linux A.
It's unclear whether you're just trying to use B for added swap space, or if you want B to actually run code.
If it's the former, all you have to do is allocate a lot of disk space on B, and NFS export it to A, and then have A mount it (you might need to use a loopback mount of a file on the NFS partition and then 'swapon' the loopback - I dont think swapon will directly take an NFS file)
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The problem is "how can i return address of VMA created on LINUX B to Linux A , and use this space ?".
If you're trying to get B to actually run code, it gets a lot more messy, as you have to worry about open file descriptors, race conditions, and many other things.
Signature · 3 lines
Valdis Kletnieks Computer Systems Senior Engineer Virginia Tech
Quoted 8 lines · User &
Hi Valdis
Create a new VMA on Linux B for Linux A is easy , but i have a problem , the address of VMA is returned on Linux B , so the VMA created on Linux B can not be used for process of linux A.
The problem is "how can i return address of VMA created on LINUX B to Linux A , and use this space ?".
What you're looking for is openmosix. It does process migration and so on..
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Thanks
BrenoOn Thu, 23 Jan 2003 11:55:38 -0500, Valdis.Kletnieks wrote
Quoted 6 lines
Quoted 3 lines · User &
I have one idea , and this is about expand virtual memory on linux boxes connected in LAN.
Example: Linux A is processing come information , and need more memory ,so
Quoted 10 lines
Quoted 1 line
with this source , Linux A could access virtual memory on Linux B in LAN.
We've seen *this* done before (remember diskless Sun3-50's?) - the
/dev/swapfile would be a large file on an NFS mount from a server. At the time, this actually made performance sense, because the old 'Shoebox' drives the -50 came with were incredibly slow, and you could actually do an NFS operation to a larger server (a -280 with Fujitsu SuperEagle disks, for instance) faster than talking to the local disk.Quoted 4 lines
These days, it's probably easier and cheaper to just buy more RAM and/or disk for Linux A.
Quoted 1 line
But i don´t know how translate the virtual address between Linux A and
B , to
Quoted 1 line
Quoted 1 line
have success in acess VM, or how to send all the process for Linux B to
be
Quoted 11 lines
Quoted 1 line
processed.
Sending the whole process to Linux B to be processed is called "process migration", and is a difficult problem. Moving the memory image of the process is usually pretty easy. What is difficult is moving things like references to open files, file locks, and so on (what if the process is actively writing to block 739 of
/usr/foo/some.file, and the LinuxB machine doesn't have a/usr/foo, or the permissions on some.file don't match, or another process has it locked, or... ) There be nasty dragons in this.Quoted 5 lines
You're probably better off buying more RAM and disk for your A machine.
Signature · 3 lines
Valdis Kletnieks Computer Systems Senior Engineer Virginia Tech----------------------
WebMail Bandnet.com.br-
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Signature · 1 line
Thomas Cataldo <[email protected]>
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I have one idea , and this is about expand virtual memory on linux boxes connected in LAN.
...
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Any ideas ?
try SCI ? -- eg., http://sci-serv.inrialpes.fr/
kenji
Quoted 9 lines · User &
I have one idea , and this is about expand virtual memory on linux boxes connected in LAN.
Example: Linux A is processing come information , and need more memory , so with this source , Linux A could access virtual memory on Linux B in LAN. But i don´t know how translate the virtual address between Linux A and B , to have success in acess VM, or how to send all the process for Linux B to be processed.Any ideas ?
1 - NFS mount a big file and use that from swap space
2 - you could try the network block device stuff, at one time I believe I had that working with RAID-1
Signature · 3 lines
bill davidsen <[email protected]> CTO, TMR Associates, Inc Doing interesting things with little computers since 1979.
Quoted 23 lines · User &
Hi all
I have one idea , and this is about expand virtual memory on linux boxes connected in LAN.
Example: Linux A is processing come information , and need more memory , so with this source , Linux A could access virtual memory on Linux B in LAN. But i don´t know how translate the virtual address between Linux A and B , to have success in acess VM, or how to send all the process for Linux B to be processed.Any ideas ?
Thanks
Breno----------------------
WebMail Bandnet.com.br-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Signature · 1 line
Patrizio Bruno <[email protected]>