Support go heapdumps from 1.7+ #6
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| log.Fatal(err) | ||
| } | ||
| return b | ||
| return []byte(x.Contents) |
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This does a copy of the contents for every call. Probably you want to keep the Contents as a []byte.
| offset int64 // position of object contents in dump file | ||
| Addr uint64 | ||
| Addr uint64 | ||
| Fields []Field |
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This will definitely lead to a larger object record. That's the limiting factor for how big a heap dump this code can process. Maybe there is a better way?
| // map from itab address whether the data field of an iface | ||
| // with that itab contains a pointer. | ||
| ItabMap map[uint64]bool | ||
| // map from the address of an interface to the address of the type |
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Substitute "an interface" with "an itab".
It's not the address of the interface itself.
| @@ -536,34 +522,23 @@ func rawRead(filename string) *Dump { | |||
| if err != nil { | |||
| log.Fatal(err) | |||
| } | |||
| if prefix || string(hdr) != "go1.3 heap dump" { | |||
| log.Fatal("not a go1.3 heap dump file") | |||
| if prefix || string(hdr) != "go1.7 heap dump" { | |||
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This is not adding 1.7 support, it is removing 1.3 support and adding 1.7 support. I'd rather add functionality instead of replacing it (even if that means more complicated parsing here).
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Thanks for the feedback. I found the same thing digging through history re: type info. I definitely opened this prematurely. It did happen to parse everything so I just wanted to get it up. I can go back and make this support multiple formats, though without the type information I don't know how useful 1.5+ heapdumps are, either to me or anyone else. |
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Yes, since 1.4 there just isn't enough type info recorded by the runtime during allocation. The heap dump contents reflect that. We're moving to a new model where functionality like this is provided by standard core dumps. There we have DWARF information so we can do a better job reconstructing types. You might want to check out the new tool and libraries: |
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@randall77 following up on this, viewcore looks great, but where can I give feedback/ask qs? |
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The standard Go issue tracker can be used to report issues. |
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@randall77 I think we a lot of people find this thread looking for an alternative to: that allows to dump the heap without stopping the process to inspect it later using |
Update the reader to support the newest heapdump format, based on https://github.com/golang/go/wiki/heapdump15-through-heapdump17
Trying to figure out how to get the type information of objects.