gnufx

14 ms·

181.
by gnufx 4y ago
Definitely <sigh>, particularly as Kerberos provides general single sign-on, rather than the uniform sign-on (just the same credentials for different services) that's typically labelled "SSO". SSH GSSAPI seems pretty s
182.
Interop: One Protocol to Rule Them All? [pdf](cl.cam.ac.uk)
3 points by gnufx 4y ago|0 comments
183.
by gnufx 4y ago
The need for HPC specifics is definitely oversold, if not by Spack. One thing is the need for proper package management for unprivileged users if they don't use container messes, and the fact that there's so much stuff to share r
184.
by gnufx 4y ago
Yes, I've found it increasingly frustrating after managing a university central HPC system with rpms. (It's a myth that you can't support different versions with rpm or dpkg if necessary.) I was at least convinced of the ne
185.
by gnufx 4y ago
I don't know specifically how Dated it is, but https://people.csail.mit.edu/jaffer/slib/Relational-Database... might also be of interest.
186.
by gnufx 4y ago
FP2 is currently supported at Android R by /e/: https://doc.e.foundation/devices/FP2
187.
Twitter can’t protect you from trolls any more, insiders say(bbc.com)
16 points by gnufx 4y ago|9 comments
188.
by gnufx 4y ago
> runs on what feels like Ubuntu LTS only It surely runs in the Cray environment (I assume still based on SuSE) on Frontier. There is ROCm packaging in Fedora/EPEL, provided by an AMD employee, but I don't know anything about
189.
Bugs Still Considered Harmful(lightbluetouchpaper.org)
2 points by gnufx 4y ago|0 comments
190.
by gnufx 4y ago
I remember it being pretty interesting when the book (manual?) on it was passed round locally.
191.
by gnufx 4y ago
> Not sure about Fortran. There was -- used for scientific computing on things like the Meiko Computing Surface, though not by me.
192.
by gnufx 4y ago
Single-user, single-program doesn't seem very Unix-y to me: https://en.wikipedia.org/wiki/CNK_operating_system There was also Plan 9, but I don't know if it was ever actually used: https://doc.cat-
193.
by gnufx 4y ago
That's reporting better figures with general compression than I'd expect from experience. Anyway, I'd expect to reach for zfp.io for arrays of floating point data. It's certainly an old observation that the compression
194.
by gnufx 4y ago
What things typically fail? (Nothing I've noticed on an HPC system running a few desktop-ish things under x2go.)
195.
by gnufx 4y ago
The competition probably shouldn't be full Unix, and in Blue Gene, for instance, it wasn't on the compute nodes. I don't know exactly what the current Cray environment is like -- it used to be rather odd -- but most HPC syste
196.
by gnufx 4y ago
In what version(s) does that tunable work? I don't see evidence of it in RHEL8 or Debian 11 (where /lib64/ld-linux-x86-64.so.2 --list-tunables doesn't work).
197.
by gnufx 4y ago
Definitely there's a lack of shared wisdom about tuning parameters (along with other things in HPC, at least in the circles I see), and too much churn with Linux v. userland (e.g. cgroups). Actually, I was forgetting the stupidity of t
198.
by gnufx 4y ago
I agree about huge pages in HPC, but regarding Linux -- if you want high performance (at least on a system designed for differing workloads), surely you should expect to do performance engineering. Whether or not you should be doing HPC on
199.
by gnufx 4y ago
As I commented on another huge pages item, you don't always want to allocate memory with malloc -- specifically putting your Fortran arrays on the stack. Note that in current Debian the THP default is "always". Also "P
200.
by gnufx 4y ago
People seem to be assuming that only malloc'ed memory is relevant. At least for Fortran, you want to allocate arrays on the stack (gfortran -fstack-arrays). Apart from using larger/huge pages, you may want to take steps to minimi
201.
by gnufx 4y ago
The default in current Debian is on: $ cat /sys/kernel/mm/transparent_hugepage/enabled [always] madvise never $ grep HUGEPAGE /boot/config-5.10.0-20-amd64 CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION=
202.
by gnufx 4y ago
What I remember was losing it just at a crucial point in the PXE boot process. You're also dependent on the same switches as the main net, and have to rely on fragile firewalling or VLANs to restrict access to the BMCs.
203.
by gnufx 4y ago
That's common, and something to avoid. You want a physically separate BMC network for security and reliability.
204.
by gnufx 4y ago
Long ago we had a contrasting experience. It had been assumed that the implemented "database" (not a general database) for storing nuclear spectroscopy data was needed because the filesystem was too slow. However, one of our &qu
205.
by gnufx 4y ago
As I implied, we're normally interested in FMA for speed, not numerical properties. I don't know in what circumstances GCC wouldn't use it when vectorizing, but I haven't seen them.
206.
by gnufx 4y ago
GCC doesn't default to non-conforming behaviour like -ffast-math -- that's Intel (at least a similar option). That's usually why people mistakenly think GCC vectorization is deficient if they don't use -funsafe-math-opt
207.
by gnufx 4y ago
Why is it crazy? Some of us don't want to lose a factor of two on linear algebra (and also care about correctness). I remember testing for correctness against Kahan's tests after FMA became available in RS/6000.
208.
by gnufx 4y ago
Others I know of: MMM (CAML Light with applets, '90s), Emacs/W3 (which Bill Perry claimed had the first CSS implementation), Abaco (Plan9)
209.
Liverpool computer scientists improve Python sorting function(news.liverpool.ac.uk)
2 points by gnufx 4y ago|1 comments
210.
by gnufx 4y ago
It looks as if it may have passed through Communications fairly unscathed.

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