On Tue, Jan 14, 2020 at 9:28 AM Lewis Tian <tasei...@gmail.com> wrote:
> When I run pagerank on Ubuntu, the code works fine. (the graph data is
> stored in web-NotreDame.txt, 21M)
>
21M isn't very large, it shouldn't present any special problems. We
probably have a bug that isn't just about file size:
> taseikyo@ubuntu:~/Desktop/osv/apps/my-pagerank-test$ ls
> Makefile module.py pagerank.c usr.manifest web-NotreDame.txt
>
> taseikyo@ubuntu:~/Desktop/osv/apps/my-pagerank-test$ make
> cc -pie -o pagerank pagerank.c
>
> taseikyo@ubuntu:~/Desktop/osv/apps/my-pagerank-test$ ll -h
> total 21M
> drwxrwxr-x 2 taseikyo taseikyo 4.0K Jan 14 11:59 ./
> drwxrwxr-x 128 taseikyo taseikyo 4.0K Jan 14 11:51 ../
> -rw-rw-r-- 1 taseikyo taseikyo 110 Jan 14 11:51 Makefile
> -rw-rw-r-- 1 taseikyo taseikyo 60 Jan 13 11:26 module.py
> -rwxrwxr-x 1 taseikyo taseikyo 17K Jan 14 11:59 pagerank*
> -rw-rw-r-- 1 taseikyo taseikyo 5.6K Jan 14 11:51 pagerank.c
> -rw-rw-r-- 1 taseikyo taseikyo 85 Jan 14 11:53 usr.manifest
> -rw-rw-r-- 1 taseikyo taseikyo 21M Jan 14 11:54 web-NotreDame.txt
>
> taseikyo@ubuntu:~/Desktop/osv/apps/my-pagerank-test$ ./pagerank
> Graph data:
>
> Nodes: 325729, Edges: 1497134
>
>
> Number of iteration to converge: 52
>
> Final Pagerank values:
> [0.002066 , 0.000181 , ...]
>
> Time spent: 0.896491 seconds.
>
> But when I build and run pagerank on osv, it fails to read the graph data
> (only read part of the graph).
>
> taseikyo@ubuntu:~/Desktop/osv$ ./scripts/build image=my-pagerank-test
> taseikyo@ubuntu:~/Desktop/osv$ ./scripts/run.py
> OSv v0.54.0-71-g69a0ce39
> eth0: 192.168.122.15
> Booted up in 338.86 ms
> Cmdline: /pagerank
>
> Graph data:
>
> Nodes: 325729, Edges: 1497134
>
> Fail to read data...
>
> From: 6 To: 119
>
> Here is part of the code:
>
> while (!feof(fp)) {
> fret = fscanf(fp, "%d%d", &fromnode, &tonode);
> if (fret == 0) {
> printf("Fail to read data...\n");
> printf("\n From: %d To: %d\n",fromnode, tonode);
> return -1;
> }
> ...
> }
>
>
Maybe we have a bug in fscanf or in the stdio reading layer?
Things I'd like you to please check:
1. Print a failure already if fret < 2 - since 1 is also a failure.
2. On failure, please print ftell(fp) - our position in the file (is it the
end? something in the middle?). Please also do a fgets() or a short fgetc()
loop or fread() to read the next available bytes, to try to understand by
fscanf() failed. Is the reading from the file failing, or is the parsing
failing?
> When I use a small graph (4 nodes, 7 edges), it runs normally.
>
> taseikyo@ubuntu:~/Desktop/osv$ ./scripts/build image=my-pagerank-test
> taseikyo@ubuntu:~/Desktop/osv$ ./scripts/run.py
> OSv v0.54.0-71-g69a0ce39
> eth0: 192.168.122.15
> Booted up in 356.44 ms
> Cmdline: /pagerank
>
> Graph data:
>
> Nodes: 4, Edges: 7
>
>
> Number of iteration to converge: 41
>
> Final Pagerank values:
>
> [0.159913 , 0.144016 , 0.144016 , 0.082809 ]
>
> Time spent: 0.693802 seconds.
>
> Is osv unable to read large files (bug?) I'll appreciate your help very
> much! : )
>
> --
> You received this message because you are subscribed to the Google Groups
> "OSv Development" group.
> To unsubscribe from this group and stop receiving emails from it, send an
> email to osv-dev+unsubscr...@googlegroups.com.
> To view this discussion on the web visit
> https://groups.google.com/d/msgid/osv-dev/50f3a073-e364-484c-803e-570e0dd6530c%40googlegroups.com
> <https://groups.google.com/d/msgid/osv-dev/50f3a073-e364-484c-803e-570e0dd6530c%40googlegroups.com?utm_medium=email&utm_source=footer>
> .
>
--
You received this message because you are subscribed to the Google Groups "OSv
Development" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to osv-dev+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/osv-dev/CANEVyjsW9R2vhi-LA276U8Y3-Mp3bG0nZTEOKAKb9gYfnj8t%2BQ%40mail.gmail.com.
