Merge branch 'master' of bscpm02.bsc.es:rarias/bscpkgs
This commit is contained in:
commit
2f56488197
@ -2,23 +2,45 @@
|
|||||||
stdenv
|
stdenv
|
||||||
, nanos6
|
, nanos6
|
||||||
, mpi
|
, mpi
|
||||||
|
, openmpi
|
||||||
|
, impi
|
||||||
, tampi
|
, tampi
|
||||||
, mcxx
|
, mcxx
|
||||||
, icc
|
, gnuDef
|
||||||
|
, intelDef
|
||||||
|
, cc
|
||||||
|
, gitBranch
|
||||||
}:
|
}:
|
||||||
|
|
||||||
|
assert (mpi == impi || mpi == openmpi);
|
||||||
|
|
||||||
|
let
|
||||||
|
mpiName = (if mpi == openmpi then
|
||||||
|
"OpenMPI"
|
||||||
|
else
|
||||||
|
"IntelMPI");
|
||||||
|
|
||||||
|
compName = (if cc == intelDef then
|
||||||
|
"Intel"
|
||||||
|
else
|
||||||
|
"GNU");
|
||||||
|
|
||||||
|
in
|
||||||
stdenv.mkDerivation rec {
|
stdenv.mkDerivation rec {
|
||||||
name = "creams";
|
name = "creams";
|
||||||
|
|
||||||
|
# src = /home/Computational/pmartin1/creams-simplified;
|
||||||
src = builtins.fetchGit {
|
src = builtins.fetchGit {
|
||||||
url = "ssh://git@bscpm02.bsc.es/pmartin1/creams-simplified.git";
|
url = "ssh://git@bscpm02.bsc.es/pmartin1/creams-simplified.git";
|
||||||
ref = "MPI+OmpSs-2+TAMPI";
|
ref = "${gitBranch}";
|
||||||
};
|
};
|
||||||
|
|
||||||
|
programPath = "/bin/creams.exe";
|
||||||
|
|
||||||
buildInputs = [
|
buildInputs = [
|
||||||
nanos6
|
nanos6
|
||||||
mpi
|
mpi
|
||||||
icc
|
cc
|
||||||
tampi
|
tampi
|
||||||
mcxx
|
mcxx
|
||||||
];
|
];
|
||||||
@ -27,12 +49,19 @@ stdenv.mkDerivation rec {
|
|||||||
|
|
||||||
configurePhase = ''
|
configurePhase = ''
|
||||||
export TAMPI_HOME=${tampi}
|
export TAMPI_HOME=${tampi}
|
||||||
|
|
||||||
. etc/bashrc
|
. etc/bashrc
|
||||||
|
|
||||||
|
export FORTRAN_COMPILER=${compName}
|
||||||
|
export MPI_LIB=${mpiName}
|
||||||
|
|
||||||
|
echo
|
||||||
|
|
||||||
|
CREAMS_UPDATE_ENVIRONMENT
|
||||||
'';
|
'';
|
||||||
|
|
||||||
installPhase = ''
|
installPhase = ''
|
||||||
mkdir -p $out/bin
|
mkdir -p $out/bin
|
||||||
cp -a build/* $out/bin
|
cp -a build/* $out/bin
|
||||||
'';
|
'';
|
||||||
|
|
||||||
}
|
}
|
||||||
|
31
garlic/creams/input.nix
Normal file
31
garlic/creams/input.nix
Normal file
@ -0,0 +1,31 @@
|
|||||||
|
{
|
||||||
|
stdenv
|
||||||
|
, granul ? 0
|
||||||
|
, nprocz ? 0
|
||||||
|
, gitBranch
|
||||||
|
}:
|
||||||
|
|
||||||
|
stdenv.mkDerivation rec {
|
||||||
|
name = "creams-input";
|
||||||
|
|
||||||
|
# src = /home/Computational/pmartin1/creams-simplified;
|
||||||
|
src = builtins.fetchGit {
|
||||||
|
url = "ssh://git@bscpm02.bsc.es/pmartin1/creams-simplified.git";
|
||||||
|
ref = "${gitBranch}";
|
||||||
|
};
|
||||||
|
|
||||||
|
phases = [ "unpackPhase" "patchPhase" "installPhase" ];
|
||||||
|
|
||||||
|
patchPhase = ''
|
||||||
|
patchShebangs SodTubeBenchmark/gridScript.sh
|
||||||
|
'';
|
||||||
|
|
||||||
|
installPhase = ''
|
||||||
|
pushd SodTubeBenchmark
|
||||||
|
./gridScript.sh 0 0 ${toString nprocz} ${toString granul}
|
||||||
|
popd
|
||||||
|
|
||||||
|
mkdir -p $out
|
||||||
|
cp -a SodTubeBenchmark $out/
|
||||||
|
'';
|
||||||
|
}
|
180
garlic/exp/creams/ss+hybrid.nix
Normal file
180
garlic/exp/creams/ss+hybrid.nix
Normal file
@ -0,0 +1,180 @@
|
|||||||
|
{
|
||||||
|
stdenv
|
||||||
|
, nixpkgs
|
||||||
|
, pkgs
|
||||||
|
, genApp
|
||||||
|
, genConfigs
|
||||||
|
, runWrappers
|
||||||
|
}:
|
||||||
|
|
||||||
|
with stdenv.lib;
|
||||||
|
|
||||||
|
let
|
||||||
|
bsc = pkgs.bsc;
|
||||||
|
|
||||||
|
# Set variable configuration for the experiment
|
||||||
|
varConfig = {
|
||||||
|
cc = [ bsc.icc ]; # [ bsc.icc pkgs.gfortran10 ];
|
||||||
|
|
||||||
|
mpi = [ bsc.impi ]; # [ bsc.impi bsc.openmpi-mn4 ];
|
||||||
|
|
||||||
|
input = [
|
||||||
|
{ nodes=1 ; nprocz=2 ; granul=37; time= "10:00:00"; }
|
||||||
|
{ nodes=2 ; nprocz=4 ; granul=19; time= "05:00:00"; }
|
||||||
|
{ nodes=4 ; nprocz=8 ; granul=10; time= "03:00:00"; }
|
||||||
|
{ nodes=8 ; nprocz=16; granul=9 ; time= "02:00:00"; }
|
||||||
|
{ nodes=16; nprocz=32; granul=9 ; time= "01:00:00"; }
|
||||||
|
];
|
||||||
|
|
||||||
|
gitBranch = [ "garlic/mpi+isend+oss+task"
|
||||||
|
"garlic/mpi+send+omp+fork"
|
||||||
|
"garlic/mpi+send+oss+task"
|
||||||
|
"garlic/tampi+isend+oss+task"
|
||||||
|
];
|
||||||
|
};
|
||||||
|
|
||||||
|
# Common configuration
|
||||||
|
common = {
|
||||||
|
# Resources
|
||||||
|
ntasksPerNode = 2;
|
||||||
|
#ntasksPerSocket = 1; // Add this variable to nix
|
||||||
|
|
||||||
|
# Stage configuration
|
||||||
|
enableSbatch = true;
|
||||||
|
enableControl = true;
|
||||||
|
enableExtrae = false;
|
||||||
|
enablePerf = false;
|
||||||
|
enableCtf = false;
|
||||||
|
|
||||||
|
# MN4 path
|
||||||
|
nixPrefix = "/gpfs/projects/bsc15/nix";
|
||||||
|
};
|
||||||
|
|
||||||
|
# Compute the cartesian product of all configurations
|
||||||
|
configs = map (conf: conf // common) (genConfigs varConfig);
|
||||||
|
|
||||||
|
stageProgram = stage:
|
||||||
|
if stage ? programPath
|
||||||
|
then "${stage}${stage.programPath}" else "${stage}";
|
||||||
|
|
||||||
|
w = runWrappers;
|
||||||
|
|
||||||
|
sbatch = {stage, conf, ...}: with conf; w.sbatch {
|
||||||
|
nodes = input.nodes;
|
||||||
|
program = stageProgram stage;
|
||||||
|
exclusive = true;
|
||||||
|
time = input.time;
|
||||||
|
#qos = "debug";
|
||||||
|
jobName = "creams-ss-${toString input.nodes}-${toString gitBranch}";
|
||||||
|
inherit nixPrefix ntasksPerNode;
|
||||||
|
};
|
||||||
|
|
||||||
|
control = {stage, conf, ...}: with conf; w.control {
|
||||||
|
program = stageProgram stage;
|
||||||
|
};
|
||||||
|
|
||||||
|
srun = {stage, conf, ...}: with conf; w.srun {
|
||||||
|
program = stageProgram stage;
|
||||||
|
srunOptions = "--cpu-bind=verbose,socket";
|
||||||
|
inherit nixPrefix;
|
||||||
|
};
|
||||||
|
|
||||||
|
statspy = {stage, conf, ...}: with conf; w.statspy {
|
||||||
|
program = stageProgram stage;
|
||||||
|
};
|
||||||
|
|
||||||
|
perf = {stage, conf, ...}: with conf; w.perf {
|
||||||
|
program = stageProgram stage;
|
||||||
|
perfArgs = "sched record -a";
|
||||||
|
};
|
||||||
|
|
||||||
|
nixsetup = {stage, conf, ...}: with conf; w.nixsetup {
|
||||||
|
program = stageProgram stage;
|
||||||
|
nixsetup = "${nixPrefix}/bin/nix-setup";
|
||||||
|
};
|
||||||
|
|
||||||
|
extrae = {stage, conf, ...}: w.extrae {
|
||||||
|
program = stageProgram stage;
|
||||||
|
traceLib = "mpi"; # mpi -> libtracempi.so
|
||||||
|
configFile = ./extrae.xml;
|
||||||
|
};
|
||||||
|
|
||||||
|
ctf = {stage, conf, ...}: w.argv {
|
||||||
|
program = stageProgram stage;
|
||||||
|
env = ''
|
||||||
|
export NANOS6=ctf
|
||||||
|
export NANOS6_CTF2PRV=0
|
||||||
|
'';
|
||||||
|
};
|
||||||
|
|
||||||
|
bscOverlay = import ../../../overlay.nix;
|
||||||
|
|
||||||
|
genPkgs = newOverlay: nixpkgs {
|
||||||
|
overlays = [
|
||||||
|
bscOverlay
|
||||||
|
newOverlay
|
||||||
|
];
|
||||||
|
};
|
||||||
|
|
||||||
|
inputDataset = {stage, conf, ...}:
|
||||||
|
let
|
||||||
|
input = bsc.garlic.creamsInput.override {
|
||||||
|
gitBranch = conf.gitBranch;
|
||||||
|
granul = conf.input.granul;
|
||||||
|
nprocz = conf.input.nprocz;
|
||||||
|
};
|
||||||
|
in w.argv
|
||||||
|
{
|
||||||
|
program = stageProgram stage;
|
||||||
|
env = ''
|
||||||
|
cp -r ${input}/SodTubeBenchmark/* .
|
||||||
|
chmod +w -R .
|
||||||
|
'';
|
||||||
|
};
|
||||||
|
|
||||||
|
# We may be able to use overlays by invoking the fix function directly, but we
|
||||||
|
# have to get the definition of the bsc packages and the garlic ones as
|
||||||
|
# overlays.
|
||||||
|
|
||||||
|
creamsFn = {stage, conf, ...}: with conf;
|
||||||
|
let
|
||||||
|
# We set the mpi implementation to the one specified in the conf, so all
|
||||||
|
# packages in bsc will use that one.
|
||||||
|
customPkgs = genPkgs (self: super: {
|
||||||
|
bsc = super.bsc // { mpi = conf.mpi; };
|
||||||
|
});
|
||||||
|
in
|
||||||
|
customPkgs.bsc.garlic.creams.override {
|
||||||
|
inherit cc mpi gitBranch;
|
||||||
|
};
|
||||||
|
|
||||||
|
stages = with common; []
|
||||||
|
# Use sbatch to request resources first
|
||||||
|
++ optional enableSbatch sbatch
|
||||||
|
|
||||||
|
# Repeats the next stages N times
|
||||||
|
++ optionals enableControl [ nixsetup control ]
|
||||||
|
|
||||||
|
# Executes srun to launch the program in the requested nodes, and
|
||||||
|
# immediately after enters the nix environment again, as slurmstepd launches
|
||||||
|
# the next stages from outside the namespace.
|
||||||
|
++ [ srun nixsetup ]
|
||||||
|
|
||||||
|
# Intrumentation with extrae
|
||||||
|
++ optional enableExtrae extrae
|
||||||
|
|
||||||
|
# Optionally profile the next stages with perf
|
||||||
|
++ optional enablePerf perf
|
||||||
|
|
||||||
|
# Optionally profile nanos6 with the new ctf
|
||||||
|
++ optional enableCtf ctf
|
||||||
|
|
||||||
|
# Execute the app with the argv and env vars
|
||||||
|
++ [ inputDataset creamsFn ];
|
||||||
|
|
||||||
|
# List of actual programs to be executed
|
||||||
|
jobs = map (conf: w.stagen { inherit conf stages; }) configs;
|
||||||
|
|
||||||
|
in
|
||||||
|
# We simply run each program one after another
|
||||||
|
w.launch jobs
|
176
garlic/exp/creams/ss+pure.nix
Normal file
176
garlic/exp/creams/ss+pure.nix
Normal file
@ -0,0 +1,176 @@
|
|||||||
|
{
|
||||||
|
stdenv
|
||||||
|
, nixpkgs
|
||||||
|
, pkgs
|
||||||
|
, genApp
|
||||||
|
, genConfigs
|
||||||
|
, runWrappers
|
||||||
|
}:
|
||||||
|
|
||||||
|
with stdenv.lib;
|
||||||
|
|
||||||
|
let
|
||||||
|
bsc = pkgs.bsc;
|
||||||
|
|
||||||
|
# Set variable configuration for the experiment
|
||||||
|
varConfig = {
|
||||||
|
cc = [ bsc.icc ]; # [ bsc.icc pkgs.gfortran10 ];
|
||||||
|
|
||||||
|
mpi = [ bsc.impi ]; # [ bsc.impi bsc.openmpi-mn4 ];
|
||||||
|
|
||||||
|
input = [
|
||||||
|
{ nodes=1 ; nprocz=48 ; granul=0; time= "10:00:00"; }
|
||||||
|
{ nodes=2 ; nprocz=96 ; granul=0; time= "05:00:00"; }
|
||||||
|
{ nodes=4 ; nprocz=192; granul=0; time= "03:00:00"; }
|
||||||
|
{ nodes=8 ; nprocz=384; granul=0; time= "02:00:00"; }
|
||||||
|
{ nodes=16; nprocz=768; granul=0; time= "01:00:00"; }
|
||||||
|
];
|
||||||
|
|
||||||
|
gitBranch = [ "garlic/mpi+send+seq" ];
|
||||||
|
};
|
||||||
|
|
||||||
|
# Common configuration
|
||||||
|
common = {
|
||||||
|
# Resources
|
||||||
|
ntasksPerNode = 48;
|
||||||
|
#ntasksPerSocket = 24; // Add this variable to nix
|
||||||
|
|
||||||
|
# Stage configuration
|
||||||
|
enableSbatch = true;
|
||||||
|
enableControl = true;
|
||||||
|
enableExtrae = false;
|
||||||
|
enablePerf = false;
|
||||||
|
enableCtf = false;
|
||||||
|
|
||||||
|
# MN4 path
|
||||||
|
nixPrefix = "/gpfs/projects/bsc15/nix";
|
||||||
|
};
|
||||||
|
|
||||||
|
# Compute the cartesian product of all configurations
|
||||||
|
configs = map (conf: conf // common) (genConfigs varConfig);
|
||||||
|
|
||||||
|
stageProgram = stage:
|
||||||
|
if stage ? programPath
|
||||||
|
then "${stage}${stage.programPath}" else "${stage}";
|
||||||
|
|
||||||
|
w = runWrappers;
|
||||||
|
|
||||||
|
sbatch = {stage, conf, ...}: with conf; w.sbatch {
|
||||||
|
nodes = input.nodes;
|
||||||
|
program = stageProgram stage;
|
||||||
|
exclusive = true;
|
||||||
|
time = input.time;
|
||||||
|
#qos = "debug";
|
||||||
|
jobName = "creams-ss-${toString input.nodes}-${toString gitBranch}";
|
||||||
|
inherit nixPrefix ntasksPerNode;
|
||||||
|
};
|
||||||
|
|
||||||
|
control = {stage, conf, ...}: with conf; w.control {
|
||||||
|
program = stageProgram stage;
|
||||||
|
};
|
||||||
|
|
||||||
|
srun = {stage, conf, ...}: with conf; w.srun {
|
||||||
|
program = stageProgram stage;
|
||||||
|
srunOptions = "--cpu-bind=verbose,rank";
|
||||||
|
inherit nixPrefix;
|
||||||
|
};
|
||||||
|
|
||||||
|
statspy = {stage, conf, ...}: with conf; w.statspy {
|
||||||
|
program = stageProgram stage;
|
||||||
|
};
|
||||||
|
|
||||||
|
perf = {stage, conf, ...}: with conf; w.perf {
|
||||||
|
program = stageProgram stage;
|
||||||
|
perfArgs = "sched record -a";
|
||||||
|
};
|
||||||
|
|
||||||
|
nixsetup = {stage, conf, ...}: with conf; w.nixsetup {
|
||||||
|
program = stageProgram stage;
|
||||||
|
nixsetup = "${nixPrefix}/bin/nix-setup";
|
||||||
|
};
|
||||||
|
|
||||||
|
extrae = {stage, conf, ...}: w.extrae {
|
||||||
|
program = stageProgram stage;
|
||||||
|
traceLib = "mpi"; # mpi -> libtracempi.so
|
||||||
|
configFile = ./extrae.xml;
|
||||||
|
};
|
||||||
|
|
||||||
|
ctf = {stage, conf, ...}: w.argv {
|
||||||
|
program = stageProgram stage;
|
||||||
|
env = ''
|
||||||
|
export NANOS6=ctf
|
||||||
|
export NANOS6_CTF2PRV=0
|
||||||
|
'';
|
||||||
|
};
|
||||||
|
|
||||||
|
bscOverlay = import ../../../overlay.nix;
|
||||||
|
|
||||||
|
genPkgs = newOverlay: nixpkgs {
|
||||||
|
overlays = [
|
||||||
|
bscOverlay
|
||||||
|
newOverlay
|
||||||
|
];
|
||||||
|
};
|
||||||
|
|
||||||
|
inputDataset = {stage, conf, ...}:
|
||||||
|
let
|
||||||
|
input = bsc.garlic.creamsInput.override {
|
||||||
|
gitBranch = conf.gitBranch;
|
||||||
|
granul = conf.input.granul;
|
||||||
|
nprocz = conf.input.nprocz;
|
||||||
|
};
|
||||||
|
in w.argv
|
||||||
|
{
|
||||||
|
program = stageProgram stage;
|
||||||
|
env = ''
|
||||||
|
cp -r ${input}/SodTubeBenchmark/* .
|
||||||
|
chmod +w -R .
|
||||||
|
'';
|
||||||
|
};
|
||||||
|
|
||||||
|
# We may be able to use overlays by invoking the fix function directly, but we
|
||||||
|
# have to get the definition of the bsc packages and the garlic ones as
|
||||||
|
# overlays.
|
||||||
|
|
||||||
|
creamsFn = {stage, conf, ...}: with conf;
|
||||||
|
let
|
||||||
|
# We set the mpi implementation to the one specified in the conf, so all
|
||||||
|
# packages in bsc will use that one.
|
||||||
|
customPkgs = genPkgs (self: super: {
|
||||||
|
bsc = super.bsc // { mpi = conf.mpi; };
|
||||||
|
});
|
||||||
|
in
|
||||||
|
customPkgs.bsc.garlic.creams.override {
|
||||||
|
inherit cc mpi gitBranch;
|
||||||
|
};
|
||||||
|
|
||||||
|
stages = with common; []
|
||||||
|
# Use sbatch to request resources first
|
||||||
|
++ optional enableSbatch sbatch
|
||||||
|
|
||||||
|
# Repeats the next stages N times
|
||||||
|
++ optionals enableControl [ nixsetup control ]
|
||||||
|
|
||||||
|
# Executes srun to launch the program in the requested nodes, and
|
||||||
|
# immediately after enters the nix environment again, as slurmstepd launches
|
||||||
|
# the next stages from outside the namespace.
|
||||||
|
++ [ srun nixsetup ]
|
||||||
|
|
||||||
|
# Intrumentation with extrae
|
||||||
|
++ optional enableExtrae extrae
|
||||||
|
|
||||||
|
# Optionally profile the next stages with perf
|
||||||
|
++ optional enablePerf perf
|
||||||
|
|
||||||
|
# Optionally profile nanos6 with the new ctf
|
||||||
|
++ optional enableCtf ctf
|
||||||
|
|
||||||
|
# Execute the app with the argv and env vars
|
||||||
|
++ [ inputDataset creamsFn ];
|
||||||
|
|
||||||
|
# List of actual programs to be executed
|
||||||
|
jobs = map (conf: w.stagen { inherit conf stages; }) configs;
|
||||||
|
|
||||||
|
in
|
||||||
|
# We simply run each program one after another
|
||||||
|
w.launch jobs
|
@ -28,7 +28,7 @@ with stdenv.lib;
|
|||||||
let
|
let
|
||||||
|
|
||||||
sbatchOpt = name: value: optionalString (value!=null)
|
sbatchOpt = name: value: optionalString (value!=null)
|
||||||
"#SBATCH --${name}=${value}\n";
|
"#SBATCH --${name}=${toString value}\n";
|
||||||
sbatchEnable = name: value: optionalString (value!=null)
|
sbatchEnable = name: value: optionalString (value!=null)
|
||||||
"#SBATCH --${name}\n";
|
"#SBATCH --${name}\n";
|
||||||
|
|
||||||
|
41
overlay.nix
41
overlay.nix
@ -143,14 +143,20 @@ let
|
|||||||
# tampi = tampi;
|
# tampi = tampi;
|
||||||
# };
|
# };
|
||||||
#
|
#
|
||||||
# creams = callPackage ./garlic/creams {
|
creams = callPackage ./garlic/creams {
|
||||||
# stdenv = pkgs.gcc9Stdenv;
|
gnuDef = self.gfortran10 ; # Default GNU compiler version
|
||||||
# mpi = intel-mpi;
|
intelDef = self.bsc.icc ; # Default Intel compiler version
|
||||||
# tampi = tampi.override {
|
|
||||||
# mpi = intel-mpi;
|
gitBranch = "garlic/mpi+send+seq";
|
||||||
# };
|
|
||||||
# };
|
cc = self.bsc.icc; # self.bsc.icc OR self.gfortran10;
|
||||||
#
|
mpi = self.bsc.mpi; # self.bsc.mpi OR self.bsc.openmpi-mn4;
|
||||||
|
};
|
||||||
|
|
||||||
|
creamsInput = callPackage ./garlic/creams/input.nix {
|
||||||
|
gitBranch = "garlic/mpi+send+seq";
|
||||||
|
};
|
||||||
|
|
||||||
# lulesh = callPackage ./garlic/lulesh {
|
# lulesh = callPackage ./garlic/lulesh {
|
||||||
# mpi = intel-mpi;
|
# mpi = intel-mpi;
|
||||||
# };
|
# };
|
||||||
@ -231,6 +237,25 @@ let
|
|||||||
};
|
};
|
||||||
};
|
};
|
||||||
|
|
||||||
|
creams = {
|
||||||
|
ss = {
|
||||||
|
pure = callPackage ./garlic/exp/creams/ss+pure.nix {
|
||||||
|
pkgs = self // self.bsc.garlic;
|
||||||
|
nixpkgs = import <nixpkgs>;
|
||||||
|
genApp = self.bsc.garlic.genApp;
|
||||||
|
genConfigs = self.bsc.garlic.genConfigs;
|
||||||
|
runWrappers = self.bsc.garlic.runWrappers;
|
||||||
|
};
|
||||||
|
hybrid = callPackage ./garlic/exp/creams/ss+hybrid.nix {
|
||||||
|
pkgs = self // self.bsc.garlic;
|
||||||
|
nixpkgs = import <nixpkgs>;
|
||||||
|
genApp = self.bsc.garlic.genApp;
|
||||||
|
genConfigs = self.bsc.garlic.genConfigs;
|
||||||
|
runWrappers = self.bsc.garlic.runWrappers;
|
||||||
|
};
|
||||||
|
};
|
||||||
|
};
|
||||||
|
|
||||||
osu = rec {
|
osu = rec {
|
||||||
latency-internode = callPackage ./garlic/exp/osu/latency.nix { };
|
latency-internode = callPackage ./garlic/exp/osu/latency.nix { };
|
||||||
latency-intranode = callPackage ./garlic/exp/osu/latency.nix {
|
latency-intranode = callPackage ./garlic/exp/osu/latency.nix {
|
||||||
|
Loading…
Reference in New Issue
Block a user