On 21/02/13 23:38, Rasmus Lerdorf wrote:
On 02/21/2013 03:15 PM, Brendon Colby wrote:
NFS is so common for sharing files that saying "Wow, people are still
serving web files over NFS?" is like saying "Wow, people are still
using the ls command to list directory contents on Linux?" I think NFS
is still very widely used, even for sharing web files.
This is simply not true. I do have a fair bit of experience in this
field, and I don't know of any major sites that do this and I have
worked with a good chunk of the largest sites out there.
Eh??? Fortune 500 enterprises and governmental departments are pretty
conservative. NAS and SAN based iSCSI and FCoE based elastic block
storage give great performance for server-specific file-systems, but
Brendon is right: for distributed file systems, NFS and CIFS still
dominate.
I don't think the appropriate answer is "don't use NFS" because this
is ridiculous as a long term solution (NFS is common, and people are
going to use it or something similar). I think the appropriate answer
is to update PHP to use stat vs. open+fstat or doing something similar
that would be optimized for both local AND shared file systems (I
would be writing a patch instead of this email if I could).
If it is of such importance to you and you are not able to do it
yourself, then hire someone to do it. We may or may not get around to
it, but like most things in PHP, we work on what we need ourselves and I
don't think anybody here would even consider putting all their PHP files
on an NFS share when performance was important.
Again wrong. Apps developers don't do this because that want to; they
do it because the IT services group that runs the production
infrastructure has mandated standard templates for live deployment to
keep the through-life cost of providing the application infrastructure
manageable, with all sorts of bureaucratic exception processes if you
think that your app is a special case. If you are lucky then they offer
a range of EC2-like standard VM templates so that you can deploy an
EBS-based approach, but most are still in catch-up mode compared to
Amazons offerings.
If you are a GM or a American Airlines, or the NIH for example then you
will have 1,000s of applications customer facing and internal and you've
got to adopt this approach for 90+% of these applications.
What Brendon is asking for is reasonable, sensible and in relative terms
easy to implement. However, I agree that it may be more sensible to use
community effort to achieve this.
