make TX and RX could be in seperate go routines #12
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…and RX, so the TX and RX could be in separate go routine
| // if rx is true, return desc in first half of umem, 2nd half otherwise | ||
| func (xsk *Socket) GetDescs(n int, rx bool) []Desc { | ||
| if n > cap(xsk.getRXDescs) { | ||
| n = cap(xsk.getRXDescs) |
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i notice you're still accessing the RXDesc fields if rx == false (here and in the following code) before referencing the TX vars.
I think it might read better to only reference the appropriate fields (depending on rx):
if rx { ... } else { .... }
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I assume you mean line 558
start = cap(xsk.getRXDescs)
this is to determine where is start index of TX, the idea is both freeTXDescs and freeRXDescs has length of options.NumFrames, but freeRXDescs only uses index 0 to options.FillRingNumDescs and freeTXDescs only use options.FillRingNumDesc onward;
the upside of this approach is not introducing too much changes to the code, the downside is of course part of freeTXDescs and freeRXDescs are never used; but given these twojust bool slice, so memory waste here is quite small
| xsk.freeTXDescs[i] = true | ||
| } | ||
| xsk.getTXDescs = make([]Desc, 0, options.CompletionRingNumDescs) | ||
| xsk.getRXDescs = make([]Desc, 0, options.FillRingNumDescs) |
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This change to use FillRing / CompletionRing when creating the desc slices is interesting.
Still trying to reason about what it changes -- for instance, should NumFrames == CompletionRingNumDescs + FillRingNumDescs / or are they different? Do we still need a separate NumFrames option, ... ? Need to review AF_XDP docs.
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right, this PR is based on assumption that NumFrames == CompletionRingNumDescs + FillRingNumDescs; if NumFrames < CompletionRingNumDescs + FillRingNumDescs, then I don't think it gona work since NumFrames is the max number of available decs for both TX and RX; on theory NumFrames could > CompletionRingNumDescs + FillRingNumDescs, but I don't see the use case of that
split Socket.freeDescs and Socket.getDescs into two instances for TX and RX, so the TX and RX could be in separate go routine