Hi! I manage to make it work with one capability. That is, now the CCCS is stored per capability but I can't enable parallel profiling because the stacks are still shared.
Now I wanted to have one instance of each stack and cost centre per capability, so that I can track the behaviour of each capability independently. Doing that is easy in the runtime system but I found out that I also have to change the code generator in the same way. I need "emitCostCentreDecl" and "costCentreStackDecl" to declare an array of structs instead of a single struct. Can someone help me with this? 2010/6/4 Henrique Ferreiro <hferre...@udc.es>: > Hi again! > > I need some help with this. > > 2010/3/17 Simon Marlow <marlo...@gmail.com>: >> On 16/03/2010 19:34, Henrique Ferreiro wrote: >>> >>> Hello! >>> >>> I am trying to make cost centre profiling work in the threaded rts >>> build in order to use that information to better understand parallel >>> behaviour. >>> >>> Currently I am learning about the internals of GHC and I am thinking >>> about how this could be done. The main blocker is that the current >>> cost centre stack is a shared global variable. The simplest solution I >>> came up with is to convert it to a thread local variable. The problem >>> would be how to access it from the global timer. >> >> Yes, basically what you want to do is put CCCS into the StgRegs structure, >> which will make it thread-local. In the timer signal you want to bump the >> counters for the CCCS on each Capability - so just iterate through the array >> of Capabilities and bump each one. > > I tried adding a new register CCCS to StgRegTable in stg/Regs.h but > there is too much hidden knowledge in the code and it isn't working. > > I got to the point where I have changed every reference to the global > variable to this register. The problem is that it isn't getting > updated. Debugging a bit it seems that the register is used as it > should (the calls to PushCostCentre and AppendCCS from the generated > code use the correct value in CCCS) but it isn't getting stored in the > register table because every time the timer is called, the value > stored is CCS_SYSTEM, the one used in initialization. > > I tried to mimic how the other registers are implemented but there is > no documentation at all so I wasn't sure what was exactly required. > > Could someone tell where exactly I have to change things or should I > post my changes and ask about specific details? > _______________________________________________ Cvs-ghc mailing list Cvs-ghc@haskell.org http://www.haskell.org/mailman/listinfo/cvs-ghc
