0.30.2 #124

donald · 2022-03-06T13:45:48Z

support unpredictable gpu idents
new gpu policy: a100_split_3 ( 3 x 2g.10gb )
minor cleanups

Don't display the job columns we are going to remove in the next commit.

The columns were included to support job restarts. However, that has never been implemented. So remove the unused columns. Note: This change reduced the size of our mxq_job.ibd with 35824930 rows from 32GB to 24GB which is more than I've expected.

Declare functions w/o arguments explicitly to satisfy my personal aesthetics. A function declaration `void foo()` has as unspecified argument list while a function declared as `void foo(void)` has explicitly no arguments. On x86_64 this makes a slight difference on how this functions needs to be called. Because a function with an unspecified argument list might be a variadic function, the ABI requires that the caller sets %al to the number of floating point registers which might have been used to pass in floating point parameters: "For calls that may call functions that use varargs or stdargs (prototype-less calls or calls to functions containing ellipsis (...) in the declaration) %al is used as hidden argument to specify the number of vector registers used. The contents of %al do not need to match exactly the number of registers, but must be an upper bound on the number of vector registers used and is in the range 0–8 inclusive" [1] If the callee is a variadic function, the usual routine in the function prologue is to save the registers, which might have been used to pass parameters, to memory so that they can be access one-by-one in the function body via pointers or indices. To give the callee an uppper bound of the number of floating point registers used to pass parameters opens an opportunity to avoid saving unused registers. The call of foo in void foo(); void bar(void) { foo(); } might compile to something like movl $0, %eax call foo The `movl $0, %eax` instruction would not be needed if foo was defined as `void foo(void)`. Note 1: gcc avoids the unneeded instructions to set up %al with -O1 or higher O1` if the function is known to be non-variadic because it is defined in the compilation uniti where it is used. Note 2: gcc function prologue for variadic functions just checks whether %al is zero or not and either saves none or all 8 floating point registers potentially used for arguments. Note 3: An instruction to clear %al (e.g. `31 c0 : xor %eax, %eax`) might have zero runtime cost on a modern processors. This change here is not a relevant optimization. I said, this is more about aesthetics. [1]: https://refspecs.linuxfoundation.org/elf/x86_64-abi-0.99.pdf

Before we add more A100 policies, factor out common code into two separate shell functions.

Add policy to create thee 2g.10gb instances on a A100.

donald added 9 commits February 24, 2022 16:50

mxqd: Clean up usage message

35e69d7

web: Remove unused job columns

646d71c

Don't display the job columns we are going to remove in the next commit.

mysql: Remove unused job attributes

38260a5

The columns were included to support job restarts. However, that has never been implemented. So remove the unused columns. Note: This change reduced the size of our mxq_job.ibd with 35824930 rows from 32GB to 24GB which is more than I've expected.

Makefile: Add ppidcache.h dependencies

074977d

gpu-setup: Remove unused variable

f03d998

gpu_setup: Allow unpredictable gpu idents

c003bf5

gpu-setup: Refactor

cdecd02

Before we add more A100 policies, factor out common code into two separate shell functions.

gpu-setup: Add policy a100_split_3

ebaeac6

Add policy to create thee 2g.10gb instances on a A100.

donald merged commit 6050cf3 into master Mar 6, 2022

0.30.2 #124

0.30.2 #124

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donald commented Mar 6, 2022