Messages in this thread | | | Date | Tue, 16 Oct 2007 19:23:49 +0400 | From | Vladislav Bolkhovitin <> | Subject | r8169 & TX offload |
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Hello,
I've recently bought Realtek RTL8169S-32 chip based Gigabit Ethernet card:
# lspci -vv Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8169 Gigabit Ethernet (rev 10) Subsystem: Realtek Semiconductor Co., Ltd. RTL-8169 Gigabit Ethernet Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV+ VGASnoop- ParErr- Stepping- SERR+ FastB2B- Status: Cap+ 66MHz+ UDF- FastB2B+ ParErr- DEVSEL=medium >TAbort- <TAbort- <MAbort- >SERR- <PERR- Latency: 64 (8000ns min, 16000ns max), Cache Line Size 20 Interrupt: pin A routed to IRQ 10 Region 0: I/O ports at c400 [size=256] Region 1: Memory at fe9fec00 (32-bit, non-prefetchable) [size=256] Expansion ROM at fe9c0000 [disabled] [size=128K] Capabilities: [dc] Power Management version 2 Flags: PMEClk- DSI- D1+ D2+ AuxCurrent=375mA PME(D0-,D1+,D2+,D3hot+,D3cold+) Status: D0 PME-Enable- DSel=0 DScale=0 PME-
I've noticed that all TX offload features (tx-checksumming, scatter-gather and TSO) are disabled by default and should be manually enabled by ethtool. I wonder, is there any particular reason for that? Why they are not enabled by default as it was done for e1000 or tg3? Are there any hidden drawbacks in enabling them?
Those offload options are definitely work. They give in my setup (32-bit 66MHz PCI, Xeon 1.7GHz CPU, open-iscsi) CPU offload from 75% to 45% and data write throughput improvement from 55MB/s to 59MB/s.
Regards, Vlad - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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