Update SLURM instructions in fox

We no longer need to use srun to enter the allocated machine. Make sure
that the default allocation time is also specified.

Reviewed-by: Aleix Boné <abonerib@bsc.es>

.gitignore

@@ -1 +1,2 @@
-./public
+/public
+.hugo_build.lock

content/_index.md

@@ -4,19 +4,19 @@ Welcome to the jungle, a set of machines with no imposed rules that are fully
 controlled and maintained by their users.
 
 The configuration of all the machines is written in a centralized [git
-repository][config] using the Nix language for NixOS. Changes in the
+repository][jungle] using the Nix language for NixOS. Changes in the
 configuration of the machines are introduced by merge requests and pass a review
 step before being deployed.
 
-[config]: https://pm.bsc.es/gitlab/rarias/jungle
+[jungle]: https://jungle.bsc.es/git/rarias/jungle
 
-The machines have access to the large list of packages available in
-[Nixpkgs][nixpkgs] and a custom set of packages named [bscpkgs][bscpkgs],
-specifically tailored to our needs for HPC machines. Users can install their own
-packages and made them system-wide available by opening a merge request.
+All jungle machines have access to the large list of packages (>120k) available
+in [Nixpkgs][nixpkgs] and a custom set of [BSC packages][overlay] specifically
+tailored to our needs for HPC machines. Users can install any packages on their
+own or request them to be system-wide available for all users.
 
 [nixpkgs]: https://github.com/NixOS/nixpkgs
-[bscpkgs]: https://pm.bsc.es/gitlab/rarias/bscpkgs
+[overlay]: https://jungle.bsc.es/git/rarias/jungle/src/branch/master/overlay.nix
 
 We have put a lot of effort to guarantee very good reproducibility properties in
 the configuration of the machines and the software they use.

content/access/index.md

@@ -7,7 +7,7 @@ description: "Request access to the machines"
 
 To request access to the machines we will need some information:
 
-1. Which machines you want access to ([hut](/hut), [fox](/fox), owl1, owl2, eudy, koro...)
+1. Which machines you want access to ([apex](/apex), [hut](/hut), [fox](/fox), [owl1, owl2](/owl), eudy, koro...)
 1. Your user name (make sure it matches the one you use for the BSC intranet)
 1. Your real name and surname (for identification purposes)
 1. The salted hash of your login password, generated with `mkpasswd -m sha-512`

content/apex/_index.md

@@ -0,0 +1,22 @@
+---
+title: "Apex"
+description: "Login node"
+date: 2025-09-05T15:34:59+02:00
+---
+
+![Apex](apex.jpg)
+
+Picture by [Michal Klajban](https://commons.wikimedia.org/wiki/File:Aoraki_-_Mt_Cook,_Aoraki_-_Mount_Cook_National_Park,_New_Zealand.jpg),
+licensed under [CC BY-SA](https://creativecommons.org/licenses/by-sa/4.0/deed.en).
+Cropped and color corrected.
+
+Apex serves as the login node to the rest of machines in jungle. Connect to it
+by accessing `ssflogin.bsc.es`, only from the apex you will be able to see other
+machines.
+
+Use `sinfo` to see which nodes are available and `salloc` to request them (see
+the manual for more details). Avoid doing large builds or computations in apex,
+use a different node instead.
+
+The home is mounted from a hardware RAID 5 of 4 disks, and is shared across
+other machines.

content/fox/_index.md

@@ -22,19 +22,16 @@ the detailed specifications:
 ## Access
 
 To access the machine, request a SLURM session from [apex](/apex) using the `fox`
-partition. If you need the machine for performance measurements, use an
-exclusive reservation:
+partition and set the time for the reservation (the default is 1 hour). If you
+need the machine for performance measurements, use an exclusive reservation:
 
-    apex% salloc -p fox --exclusive
+    apex% salloc -p fox -t 02:00:00 --exclusive
+    fox%
 
 Otherwise, specify the CPUs that you need so other users can also use the node
 at the same time:
 
-    apex% salloc -p fox -c 8
-
-Then use srun to execute an interactive shell:
-
-    apex% srun --pty $SHELL
+    apex% salloc -p fox -t 02:00:00 -c 8
     fox%
 
 Make sure you get all CPUs you expect:
@@ -46,55 +43,38 @@ Follow [these steps](/access) if you don't have access to apex or fox.
 
 ## CUDA
 
-To use CUDA, you can use the following `flake.nix` placed in a new directory to
-load all the required dependencies:
+To use CUDA you'll need to load the NVIDIA `nvcc` compiler and some additional
+libraries in the environment. Clone the 
+[following
+example](https://jungle.bsc.es/git/rarias/devshell/src/branch/main/cuda) and
+modify the `flake.nix` if needed to add additional packages.
 
-```nix
-{
-  inputs.jungle.url = "jungle";
+Then just run `nix develop` from the same directory to spawn a new shell with
+the CUDA environment:
 
-  outputs = { jungle, ... }: {
-    devShell.x86_64-linux = let
-      pkgs = jungle.nixosConfigurations.fox.pkgs;
-    in pkgs.mkShell {
-      name = "cuda-env-shell";
-      buildInputs = with pkgs; [
-        git gitRepo gnupg autoconf curl
-        procps gnumake util-linux m4 gperf unzip
+    fox% git clone https://jungle.bsc.es/git/rarias/devshell
 
-        # Cuda packages (more at https://search.nixos.org/packages)
-        cudatoolkit linuxPackages.nvidia_x11
-        cudaPackages.cuda_cudart.static
-        cudaPackages.libcusparse
+    fox% cd devshell/cuda
 
-        libGLU libGL
-        xorg.libXi xorg.libXmu freeglut
-        xorg.libXext xorg.libX11 xorg.libXv xorg.libXrandr zlib
-        ncurses5 stdenv.cc binutils
-      ];
-      shellHook = ''
-        export CUDA_PATH=${pkgs.cudatoolkit}
-        export LD_LIBRARY_PATH=/var/run/opengl-driver/lib
-        export SMS=50
-      '';
-    };
-  };
-}
-```
+    fox% nix develop
 
-Then just run `nix develop` from the same directory:
-
-    % mkdir cuda
-    % cd cuda
-    % vim flake.nix
-    [...]
-    % nix develop
-    $ nvcc -V
+    fox$ nvcc -V
     nvcc: NVIDIA (R) Cuda compiler driver
-    Copyright (c) 2005-2024 NVIDIA Corporation
-    Built on Tue_Feb_27_16:19:38_PST_2024
-    Cuda compilation tools, release 12.4, V12.4.99
-    Build cuda_12.4.r12.4/compiler.33961263_0
+    Copyright (c) 2005-2025 NVIDIA Corporation
+    Built on Fri_Feb_21_20:23:50_PST_2025
+    Cuda compilation tools, release 12.8, V12.8.93
+    Build cuda_12.8.r12.8/compiler.35583870_0
+
+    fox$ make
+    nvcc -ccbin g++ -m64 -Wno-deprecated-gpu-targets -o cudainfo cudainfo.cpp
+
+    fox$ ./cudainfo
+    ./cudainfo Starting...
+
+     CUDA Device Query (Runtime API) version (CUDART static linking)
+
+    Detected 2 CUDA Capable device(s)
+    ...
 
 ## AMD uProf
 

content/hut/_index.md

@@ -23,7 +23,7 @@ a good candidate for low noise executions.
 We provide a binary cache in `hut`, with the aim of avoiding unnecessary
 recompilation of packages.
 
-The cache should contain common packages from bscpkgs, but we don't provide
+The cache should contain common packages from jungle, but we don't provide
 any guarantee that of what will be available in the cache, or for how long.
 We recommend following the latest version of the `jungle` flake to avoid cache
 misses.