-*- text -*-
-* The p1-4.c testcase needs significant tuning. Currently it takes
- too long (especially when SHOW_PROGRESS is turned on) and doesn't
- show significant improvement.
+* The tests in tests/ don't apply the grading patches.
-* The semantics of the join system call should change so that it only
- returns the exit code once.
+* We need better and more example programs.
+
+ - Need an mmap example program as a replacement for the crappy mmap FAQ
+ question.
+
+ - How about `diff' and `cmp' programs?
+
+* Threads:
+
+ - mlfqs tests suck. They aren't even correct, e.g. the amarv
+ submission from win0405 is graded incorrectly.
+
+* Userprog project:
+
+ - Don't emphasize that stuff needs to be copied from user space to
+ kernel space. Instead, emphasize validation and suggest that
+ copying is a common solution and that it will be necessary in
+ project 3 and in real OSes. Also revise the grading criteria to
+ match.
+
+ - Mark read-only pages as actually read-only in the page table. Or,
+ since this was consistently rated as the easiest project by the
+ students, require them to do it.
+
+ - Don't provide per-process pagedir implementation but only
+ single-process implementation and require students to implement
+ the separation? This project was rated as the easiest after all.
+ Alternately we could just remove the synchronization on pid
+ selection and check that students fix it.
+
+* VM project:
+
+ - Discuss the perils of mixing dirty bits between kernel and user virtual
+ memory.
+
+ - Sample solution.
+
+ - Update grading/vm to reflect new mmap, munmap forms.
+
+* Filesys project:
+
+ - Increase maximum disk size from 8 MB to something that actually
+ requires doubly indirect nodes. There is a negative pressure here
+ from the bitmap object--perhaps we need a specialized bitmap that
+ doesn't have to be all in-memory at once.
+
+ Alternatively, shrink the inode size.
+
+ - Add mkdir and ls example user programs.
+
+ - Add option to disable buffer cache.
+
+ - Get rid of "dump" commands--they're not really useful.
+
+ - Sample solution.
+
+ - Need a better way to measure performance improvement of buffer
+ cache. Some students reported that their system was slower with
+ cache--likely, Bochs doesn't simulate a disk with a realistic
+ speed.
+
+ - Clarify effect of remove(cwd).
+
+* Documentation:
+
+ - Finish writing tour.
+
+ - Add "Digging Deeper" sections that describe the nitty-gritty x86
+ details for the benefit of those interested.
+
+ - Add explanations of what "real" OSes do to give students some
+ perspective.
+
+* Assignments:
+
+ - Add extra credit:
+
+ . Low-level x86 stuff, like paged page tables.
+
+ . Specifics on how to implement sbrk, malloc.
+
+ . Other good ideas.
+
+ . opendir/readdir/closedir
+
+ . everything needed for getcwd()
+
+ - Add src/testcases/vm, src/testcases/filesys and make it clear to use
+ them?
+
+* Tests:
+
+ - Release some of them.
+
+ - The threads, userprog, vm test source files could use
+ factorization and cleanup along the lines of fslib in the filesys
+ tests.
+
+ - The p1-4.c testcase needs significant tuning. Currently it takes
+ too long (especially when SHOW_PROGRESS is turned on) and doesn't
+ show significant improvement.
+
+* Code:
+
+ - Make threads test use a program and arguments like the other
+ projects.
+
+ - Revise command-line arguments for sensibility instead of for
+ Nachos compatibility.
+
+ - Get rid of all compile-time flags, e.g. MLFQS should be a runtime
+ command-line option.
+
+ - Need an optimization barrier and an explanation of it in the
+ documentation.
+
+ - Need to check the wait system call more thoroughly.
+
+ - Library is not precisely standard, e.g. ptrdiff_t should not be
+ defined by stdlib.h.
projects / pintos-anon / blobdiff