school/csci5451
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

save b4 messing with shit

Browse source
This commit is contained in:
Michael Zhang 2023-10-31 00:48:27 +00:00
parent 432f17726c
commit 9d064bef0d
3 changed files with 105 additions and 44 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

3
.vscode/settings.json vendored
View file

@ -5,5 +5,6 @@
"[python]": {
"editor.defaultFormatter": "ms-python.black-formatter"
},
"python.formatting.provider": "none"
"python.formatting.provider": "none",
"discord.enabled": true
}

5
assignments/02/Makefile
View file

@ -1,4 +1,4 @@
.PHONY: all clean
.PHONY: all clean run-example
CC := cc
@ -10,6 +10,9 @@ LDFLAGS += $(shell pkg-config --libs mpi)
all: qs_mpi
run-example: qs_mpi
mpirun --allow-run-as-root -np 4 ./qs_mpi 32 output.txt
qs_mpi: qs_mpi.o
$(CC) $^ $(CFLAGS) $(LDFLAGS) -o $@

107
assignments/02/qs_mpi.c
View file

@ -18,7 +18,7 @@
void local_quicksort(int *arr, int lo, int hi);
char *string_of_list(int *arr, int len);
void recursive_quicksort(int *integers, int n, MPI_Comm comm);
void recursive_quicksort(int *integers, int n, int root, MPI_Comm comm);
int main(int argc, char **argv) {
int rank, p;
@ -33,7 +33,7 @@ int main(int argc, char **argv) {
int n_over_p = n / p;
int integers[n_over_p];
// Important implementation detail: srand(0) is specially handled by glibc to
// Minor implementation detail: srand(0) is specially handled by glibc to
// behave as if it was called with srand(1). To get around this, I'm seeding
// with rank + 1
//
@ -46,17 +46,26 @@ int main(int argc, char **argv) {
// printf(" - %d\n", integers[i]);
}
recursive_quicksort(integers, n, MPI_COMM_WORLD);
recursive_quicksort(integers, n, 0, MPI_COMM_WORLD);
sleep(1);
printf("[%d] after: %s\n", rank, string_of_list(integers, n_over_p));
// sleep(1);
// printf("[%d] after: %s\n", rank, string_of_list(integers, n_over_p));
// The first node is responsible for collecting all the data and then
// printing it out to the file MPI_Gather(const void *sendbuf, int
// sendcount, MPI_INT, void *recvbuf,
// int recvcount, MPI_INT, 0, MPI_COMM_WORLD);
int recvbuf[n];
MPI_Allgather(integers, n_over_p, MPI_INT, recvbuf, n_over_p, MPI_INT,
MPI_COMM_WORLD);
if (rank == 0) {
FILE *f = fopen(argv[2], "w");
// printf("integers: %s\n", string_of_list(recvbuf, n));
for (int i = 0; i < p; i += 1) {
printf("[%d] integers: %s\n", rank,
string_of_list(&recvbuf[i * n_over_p], n_over_p));
}
fclose(f);
}
@ -108,7 +117,7 @@ char *string_of_list(int *arr, int len) {
return buffer;
}
void recursive_quicksort(int *integers, int n, MPI_Comm comm) {
void recursive_quicksort(int *integers, int n, int root, MPI_Comm comm) {
int rank, p;
MPI_Comm_size(comm, &p);
MPI_Comm_rank(comm, &rank);
@ -116,10 +125,19 @@ void recursive_quicksort(int *integers, int n, MPI_Comm comm) {
if (p == 1) {
// Recursion base case: just sort it serially
local_quicksort(integers, 0, n);
printf("Quicksorted: %s\n", string_of_list(integers, n));
return;
}
sleep(1);
printf("\n\n");
int n_over_p_max = (n + p - 1) / p;
int n_over_p = n / p;
if (rank == root)
n_over_p += n - p * n_over_p;
printf(
"[%d] :::::::::::::::::::::::::::: RECURSIVE QUICKSORT (n=%d, n/p=%d)\n",
rank, n, n_over_p);
// Locally sort
// printf("[%d] Numbers before: %s\n", rank,
@ -131,12 +149,26 @@ void recursive_quicksort(int *integers, int n, MPI_Comm comm) {
// Select a pivot.
// This pivot is broadcasted to all nodes
int pivot;
{
// First, select a random element
int rand_el = integers[rand() % n_over_p];
// The pivot is selected as the median (see chp. 9.4.4)
// Not the real median though, need an existing element of the array
pivot = integers[n_over_p / 2];
MPI_Bcast(&pivot, 1, MPI_INT, 0, MPI_COMM_WORLD);
// printf("--- Broadcasted pivot: %d ---\n", pivot);
// Gather it
int rand_els[p];
MPI_Gather(&rand_el, 1, MPI_INT, rand_els, 1, MPI_INT, root, comm);
// Get the median
if (rank == root) {
// Sort
local_quicksort(rand_els, 0, p);
// Get the middle element
pivot = rand_els[p / 2];
}
MPI_Bcast(&pivot, 1, MPI_INT, root, comm);
}
printf("[%d] Broadcasted pivot: %d\n", rank, pivot);
// Determine where the boundary between S (lower) and L (higher) lies
int boundary;
@ -154,12 +186,12 @@ void recursive_quicksort(int *integers, int n, MPI_Comm comm) {
// Perform global arrangement
int S_global_end, L_reverse_end, S_global_max_end;
MPI_Scan(&S_size, &S_global_end, 1, MPI_INT, MPI_SUM, MPI_COMM_WORLD);
MPI_Scan(&L_size, &L_reverse_end, 1, MPI_INT, MPI_SUM, MPI_COMM_WORLD);
MPI_Scan(&S_size, &S_global_end, 1, MPI_INT, MPI_SUM, comm);
MPI_Scan(&L_size, &L_reverse_end, 1, MPI_INT, MPI_SUM, comm);
// printf("[%d] bruh %d\n", rank, S_global_end);
MPI_Reduce(&S_global_end, &S_global_max_end, 1, MPI_INT, MPI_MAX, 0,
MPI_COMM_WORLD);
// Get the boundary element between S and L
MPI_Allreduce(&S_global_end, &S_global_max_end, 1, MPI_INT, MPI_MAX, comm);
int S_global_start = S_global_end - S_size,
L_reverse_start = L_reverse_end - L_size,
@ -240,7 +272,7 @@ void recursive_quicksort(int *integers, int n, MPI_Comm comm) {
}
MPI_Alltoallv(send_ctl, ctl_send_counts, ctl_send_displs, MPI_INT, S_ctl,
recv_counts, recv_displs, MPI_INT, MPI_COMM_WORLD);
recv_counts, recv_displs, MPI_INT, comm);
}
// Send L to the correct target
@ -282,7 +314,7 @@ void recursive_quicksort(int *integers, int n, MPI_Comm comm) {
}
MPI_Alltoallv(send_ctl, ctl_send_counts, ctl_send_displs, MPI_INT, L_ctl,
recv_counts, recv_displs, MPI_INT, MPI_COMM_WORLD);
recv_counts, recv_displs, MPI_INT, comm);
}
// After sending S and L information
@ -296,9 +328,12 @@ void recursive_quicksort(int *integers, int n, MPI_Comm comm) {
// integers_recv_buf,
// recv_counts, recv_displs, MPI_INT, MPI_COMM_WORLD);
MPI_Allgather(integers, n_over_p, MPI_INT, integers_recv_buf, n_over_p,
MPI_INT, MPI_COMM_WORLD);
MPI_INT, comm);
// printf("[%d] ints: %s\n", rank, string_of_list(integers_recv_buf, n));
for (int i = 0; i < p; ++i) {
}
for (int i = 0; i < p; ++i) {
int count = S_ctl[i * CTL_SIZE];
int from_global_start = S_ctl[i * CTL_SIZE + 1];
@ -331,16 +366,20 @@ void recursive_quicksort(int *integers, int n, MPI_Comm comm) {
}
}
printf("[%d] after: %s\n", rank, string_of_list(integers, n_over_p));
// Now, determine which processes should be responsible for taking the S and L
// arrays
// Specifically, the part where it's split, break the tie to see if it goes
// down or up
int colors[p];
if (rank == 0) {
int p_of_split = S_global_max_end / n_over_p;
int split_point = S_global_max_end % n_over_p;
printf("[%d] shiet %d\n", rank, p_of_split);
// printf("[%d] p_of_split = %d / %d = %d\n", rank, S_global_max_end,
// n_over_p,
// p_of_split);
int S_split_add = split_point, L_split_sub = n_over_p - split_point;
int lo_start = 0, lo_end;
int hi_start, hi_end = p;
@ -352,16 +391,34 @@ void recursive_quicksort(int *integers, int n, MPI_Comm comm) {
lo_end = hi_start = p_of_split;
}
int child_root = -1;
for (int i = 0; i < p; ++i) {
if (i < lo_end)
colors[i] = 100;
else
else {
colors[i] = 200;
if (child_root == -1)
child_root = i;
}
}
MPI_Comm child;
MPI_Comm_split(comm, colors[rank], rank, &child);
printf("[%d] Recursing...\n", rank);
MPI_Comm_free(&child);
// MPI_Comm child;
// MPI_Comm_split(comm, colors[rank], rank, &child);
// printf("[%d] Recursing...\n", rank);
// int child_size;
// MPI_Comm_size(child, &child_size);
// int start_at = 0, new_n = child_size * n_over_p;
// if (colors[rank] == 100) {
// new_n += S_split_add;
// } else {
// new_n -= L_split_sub;
// if (rank == p_of_split)
// start_at = split_point;
// }
// recursive_quicksort(integers, n, child_root, child);
// printf("[%d] Done recursing.\n", rank);
// MPI_Comm_free(&child);
}