5 ms·

Not sure why NFS gets such a bad rap. On a low-latency network, properly tuned NFS has very few, if any performance issues. I've personally seen read/write rat

Not sure why NFS gets such a bad rap. On a low-latency network, properly tuned NFS has very few, if any performance issues. I've personally seen read/write rates exceeding 800MByte/sec on more or less white-box hardware, at which point it was limited by the underlying storage infrastructure (8Gbit fiber), not the NFS protocols. Dell has a 2013 white paper (I'm not affiliated with them, fwiw) about their fairly white box setup that achieved > 100,000 iops, 2.5GBbyte/s sequential write, and 3.5GBbyte/s sequential read: http://en.community.dell.com/techcenter/high-performance-computing/b/hpc_storage_and_file_systems/archive/2013/04/05/over-100-000-iops-with-plain-ol-nfs-and-7-200-rpm-drives http://en.community.dell.com/techcenter/high-performance-com...

eknkc 12y ago
Is it really that good? My only test case has been a VMWare virtual machine, mounting an nfs share from the host so I could work on my local filesystem and execute within the VM. Switched to a filesystem wather + rsync combo after struggling with poor random read performance. Maybe it was due to bad configuration but always thought it would be a poor choice for anything serius.
- ploxiln 12y ago
  That might be an issue with scheduling of the virtual kernel and the host kernel. I've found nfs to be much faster and more reliable than sshfs or smbfs for VMs, using either qemu-kvm on linux or virtualbox on OS X.
buster 12y ago
(me: Working in the Messaging Business for ISPs) Not sure how it would ever be technically possible for a networked filesystem to get even near directly attached storage. But, for sure, the typical carrier grade EMC or Netapp is MUCH slower then a good SAN. I'm talking about petabytes of very small (average maybe 20kB) files with lots of _random_ sync writes and reads. NFS has a lot of other benefits, but it surely is not super high performance in every usecase. Regardless of what a theoretical marketing whitepaper has shown in some lab setup. Someone who thinks that you can put a network protocol around a filesystem without _any_ performance impact is nuts. BUT if your usecase fits NFS you might as well get very good performance out of it. As always, pick the right technology for your specific case.
- dekhn 12y ago
  Petabytes of 20k files? I think you might want to use your filesystem more effectively.
  - buster 12y ago
    Well, what would it help in terms of NFS? You'd still have to tell NFS to read 20kB. If it's 20kB from one big file or one 20kB file doesn't matter much. it's common to have one file per email and the usual filesystem has no problem with that.

eknkc 12y ago

Is it really that good? My only test case has been a VMWare virtual machine, mounting an nfs share from the host so I could work on my local filesystem and execute within the VM. Switched to a filesystem wather + rsync combo after struggling with poor random read performance. Maybe it was due to bad configuration but always thought it would be a poor choice for anything serius.

ploxiln 12y ago
That might be an issue with scheduling of the virtual kernel and the host kernel. I've found nfs to be much faster and more reliable than sshfs or smbfs for VMs, using either qemu-kvm on linux or virtualbox on OS X.

buster 12y ago

(me: Working in the Messaging Business for ISPs) Not sure how it would ever be technically possible for a networked filesystem to get even near directly attached storage. But, for sure, the typical carrier grade EMC or Netapp is MUCH slower then a good SAN. I'm talking about petabytes of very small (average maybe 20kB) files with lots of _random_ sync writes and reads. NFS has a lot of other benefits, but it surely is not super high performance in every usecase. Regardless of what a theoretical marketing whitepaper has shown in some lab setup. Someone who thinks that you can put a network protocol around a filesystem without _any_ performance impact is nuts. BUT if your usecase fits NFS you might as well get very good performance out of it. As always, pick the right technology for your specific case.

dekhn 12y ago
Petabytes of 20k files? I think you might want to use your filesystem more effectively.
- buster 12y ago
  Well, what would it help in terms of NFS? You'd still have to tell NFS to read 20kB. If it's 20kB from one big file or one 20kB file doesn't matter much. it's common to have one file per email and the usual filesystem has no problem with that.