Align print format string for column names and units

[dmitrygx]

Format for column names and units started to be mismatched after changing "error" to "#wrong" in NCCL 2.13 (merged to master as a part of 51af557).

[AddyLaddy]

I can't see any misalignment in my tests:

#
#                                                              out-of-place                       in-place          
#       size         count      type   redop    root     time   algbw   busbw #wrong     time   algbw   busbw #wrong
#        (B)    (elements)                               (us)  (GB/s)  (GB/s)            (us)  (GB/s)  (GB/s)       
  1073741824     268435456     float     sum      -1   8160.7  131.58  230.26      0   8158.3  131.61  230.32      0
  2147483648     536870912     float     sum      -1    16191  132.64  232.11      0    16192  132.63  232.10      0
  4294967296    1073741824     float     sum      -1    32115  133.74  234.04      0    32106  133.77  234.10      0
  8589934592    2147483648     float     sum      -1    64086  134.04  234.57      0    64070  134.07  234.62      0
 17179869184    4294967296     float     sum      -1   128070  134.14  234.75      0   128042  134.17  234.80      0

[sjeaugey]

That's because you don't have any data corruption. In the case of corruption, we could have up to 6 chars I guess hence the change.

If that is truly the idea, I agree it would be better. It's annoying to widen the line for something that should never happen, but if it happened, it would break any automatic parsing, including parsing supposed to report errors.

[dmitrygx]

this change aligns format string:

• for column names: "# %10s %12s %8s %6s %6s %7s %6s %6s %6s %7s %6s %6s %6s\n"
• for units................:"# %10s %12s %8s %6s %6s %7s %6s %6s %5s %7s %6s %6s %5s\n"

to make them identical: "# %10s %12s %8s %6s %6s %7s %6s %6s %5s %7s %6s %6s %5s\n" and have the same width for #wrong column in units and measurements printed:

nccl-tests/src/common.cu

Line 553 in 2cbb968

PRINT(" %7s %6.2f %6.2f %5g", timeStr, algBw, busBw, (double)wrongElts);

and

nccl-tests/src/common.cu

Line 555 in 2cbb968

PRINT(" %7s %6.2f %6.2f %5s", timeStr, algBw, busBw, "N/A");

[dmitrygx]

@AddyLaddy @sjeaugey could you review pls?

[sjeaugey]

The reason we replaced %5s by %6s (removing one space and adding one char to the column name) was because we needed that extra char given #wrong is 6 chars. If you unify everything on %5s then #wrong will be too large and cause a shift of the columns by one char.

So I'm still not sure what problem we're trying to solve here.