No detail for profiling costs atributed to SYSTEM / PINNED / ARR_WORDS
When using ghc's heap profiling, some allocations are treated specially in such a way that we get no useful information for them.
- For +RTS -hc "cost centre stack", the allocations are classed as PINNED, which means we cannot see which cost centre allocated them.
- For +RTS -hm "module", the allocations are classed as SYSTEM, which means we cannot see which module allocated them.
- For +RTS -hy "type description" and +RTS -hd "closure description", the allocations are classed as ARR_WORDS, which means we cannot see what type they are (ByteArray#?).
So none of these modes help us see what these allocations are or where they come from. Do these allocations have to be treated in this special way such that we loose all useful information?
Presumably they are pinned ByteArray#s, but surely we can still track which cost centre to assign them to, and hence the module, and shouldn't the type/closure description be "ByteArray#" or "pinned ByteArray#" or something?
Trac metadata
| Trac field | Value |
|---|---|
| Version | 7.10.1 |
| Type | FeatureRequest |
| TypeOfFailure | OtherFailure |
| Priority | normal |
| Resolution | Unresolved |
| Component | Profiling |
| Test case | |
| Differential revisions | |
| BlockedBy | |
| Related | |
| Blocking | |
| CC | |
| Operating system | |
| Architecture |