mem-ruby: add option to disable GPU coalescer deadlock watchdog - #4
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Basemism wants to merge 1 commit into
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mem-ruby: add option to disable GPU coalescer deadlock watchdog#4Basemism wants to merge 1 commit into
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The GPU coalescer watchdog aborts the simulation when a request stays outstanding longer than deadlock_threshold. This false-triggers in slow-memory sensitivity experiments where DRAM timings are intentionally stretched and long-lived requests are expected. Add a disable_deadlock_check parameter to GPUCoalescer (default False, so the watchdog stays on by default) and gate the wakeup() deadlock scan on it. Expose it through GPU_VIPER's --disable-watchdog flag, wired to both VIPER coalescers.
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Add a disable_deadlock_check parameter to GPUCoalescer and gate the deadlock scan in wakeup() on this parameter. It defaults to False, keeping current behaviours unchanged.
A --disable-watchdog option is also added to GPU_VIPER, disabling the deadlock check on both GPU VIPER coalescers. Other coalescer wakeup and request-processing behaviour remains unchanged.
This is useful when investigating pathological slowdowns in gem5. In some cases, execution may still be making forward progress but take significantly longer than the watchdog threshold. Panicking as soon as the threshold is reached might mask the underlying issue and preventing the simulation from running long enough to diagnose the source of the slowdown.
(In my case detecting the 1 GiB lookup issues)