L4Re IPC share memory that share file in one Linux filesystem and be visible to other Linuxes
Hi L4,
I want to share a file in one Linux filesystem and be visible to other Linuxes that all run on top Fiasco.OC. It seems an IPC communication between L4re vm tasks. And access a file in Linux filesystem is a mechanism of kernel block device driver. But I only notice two char device drivers that use L4re library l4shmc in L4linux. It is l4ser_shm and l4shmnet. May you give some information about this work how to work. Thanks.
Joyce.peng(彭美僑)
Hi,
On 07/05/2017 05:47 AM, Joyce Peng(彭美僑) wrote:
Hi L4,
I want to share a file in one Linux filesystem and be visible to other Linuxes that all run on top Fiasco.OC. It seems an IPC communication between L4re vm tasks. And access a file in Linux filesystem is a mechanism of kernel block device driver. But I only notice two char device drivers that use L4re library l4shmc in L4linux. It is l4ser_shm and l4shmnet. May you give some information about this work how to work. Thanks.
Have you thought about how to syncronize access to the filesystem between the two VMs?
The easiest approach would be to setup a (virtual) network connection between the two VMs and let one VM provide the filesystem via NFS, NBD or SMB.
Regards, Matthias.
Joyce.peng(彭美僑)
Yes, I know this easiest way that mount filesystem via NFS, NBD or SMB. But I have a mission to evaluate the IPC performance between two Linuxes that run on top of Fiasco.OC. So our evaluated environment is run a media player in one Linux and this player will access media data in other Linux. And we use uvmm to run two vms that run Linux respectively.
Regards, Joyce.Peng(彭美僑)
-----Original Message----- From: Matthias Lange [mailto:matthias.lange@kernkonzept.com] Sent: Thursday, July 06, 2017 4:58 AM To: l4-hackers@os.inf.tu-dresden.de Cc: Joyce Peng(彭美僑) Subject: Re: L4Re IPC share memory that share file in one Linux filesystem and be visible to other Linuxes
Hi,
On 07/05/2017 05:47 AM, Joyce Peng(彭美僑) wrote:
Hi L4,
I want to share a file in one Linux filesystem and be visible to other Linuxes that all run on top Fiasco.OC. It seems an IPC communication between L4re vm tasks. And access a file in Linux filesystem is a mechanism of kernel block device driver. But I only notice two char device drivers that use L4re library l4shmc in L4linux. It is l4ser_shm and l4shmnet. May you give some information about this work how to work. Thanks.
Have you thought about how to syncronize access to the filesystem between the two VMs?
The easiest approach would be to setup a (virtual) network connection between the two VMs and let one VM provide the filesystem via NFS, NBD or SMB.
Regards, Matthias.
Joyce.peng(彭美僑)
Hi,
On 07/06/2017 02:14 PM, Joyce Peng(彭美僑) wrote:
Yes, I know this easiest way that mount filesystem via NFS, NBD or SMB. But I have a mission to evaluate the IPC performance between two Linuxes that run on top of Fiasco.OC. So our evaluated environment is run a media player in one Linux and this player will access media data in other Linux. And we use uvmm to run two vms that run Linux respectively.
Sorry, I'am a bit confused here. What do you mean if you say you want to measure IPC performance between two Linuxes? What does IPC in this context mean?
If you measure the communication performance between two Linux VMs running with uvmm you have no direct (L4) IPC between Linux processes in both VMs. You will (not only) add a lot of overhead because of VM exits and resumes.
If you are interested in raw IPC performance, why don't you just use pingpong?
Best, Matthias.
Regards, Joyce.Peng(彭美僑)
-----Original Message----- From: Matthias Lange [mailto:matthias.lange@kernkonzept.com] Sent: Thursday, July 06, 2017 4:58 AM To: l4-hackers@os.inf.tu-dresden.de Cc: Joyce Peng(彭美僑) Subject: Re: L4Re IPC share memory that share file in one Linux filesystem and be visible to other Linuxes
Hi,
On 07/05/2017 05:47 AM, Joyce Peng(彭美僑) wrote:
Hi L4,
I want to share a file in one Linux filesystem and be visible to other Linuxes that all run on top Fiasco.OC. It seems an IPC communication between L4re vm tasks. And access a file in Linux filesystem is a mechanism of kernel block device driver. But I only notice two char device drivers that use L4re library l4shmc in L4linux. It is l4ser_shm and l4shmnet. May you give some information about this work how to work. Thanks.
Have you thought about how to syncronize access to the filesystem between the two VMs?
The easiest approach would be to setup a (virtual) network connection between the two VMs and let one VM provide the filesystem via NFS, NBD or SMB.
Regards, Matthias.
Joyce.peng(彭美僑
l4-hackers@os.inf.tu-dresden.de
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Joyce Peng(彭美僑) -
Matthias Lange