Opened 4 years ago

Last modified 4 years ago

#10730 new bug

Spectral norm allocations increased 17% between 7.6 and 7.8

Reported by: bgamari Owned by:
Priority: low Milestone:
Component: Compiler Version: 7.8.3
Keywords: Cc:
Operating System: Unknown/Multiple Architecture: Unknown/Multiple
Type of failure: Runtime performance bug Test Case:
Blocked By: Blocking:
Related Tickets: Differential Rev(s):
Wiki Page:

Description (last modified by bgamari)

It appears that spectral-norm regressed rather severely from 7.6 to 7.8 in total allocations. Meanwhile the binary size also increased by 7% or so. However, it also appears that runtime was unaffected by this change.

The rule firings are very similar between 7.6 and 7.8. Three rules fire in 7.8 that do not fire in 7.6,

  1 Class op formatArg 
  1 Class op parseFormat              
  1 tagToEnum#     

The difference in allocation persists even if one reverts the Text.Printf rewrite that gives rise to the formatArg and parseFormat rules, so these can be safely ignored.

Change History (1)

comment:1 Changed 4 years ago by bgamari

Description: modified (diff)
Note: See TracTickets for help on using tickets.