From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dimosthenis Pediaditakis Date: Fri, 14 Feb 2014 01:45:15 +0000 Subject: [ath9k-devel] Interrupt mitigation for USB Atheros dongles Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ath9k-devel@lists.ath9k.org Hi all, I am using a capacity and available bandwidth measurement software that compute estimates based on the gaps among packet trains/pairs. For that reason I need to disable RX/TX interrupt mitigation for the devices that I take the measurement form, because it introduces skew, and renders unmeasurable the fast links (> 54Kbps). The less latencies the drivers+kernel introduces, the better. I have so far managed to disable all together the RX mitigation for mini-PCIe devices by hard-coding the following line in "linux/drivers/net/wireless/ath/ath9k/ hw.c" ah->config.rx_intr_mitigation = false; While the above trick improves my results, it doesn't change the behaviour of the Atheros-based USB WiFi dongles. AFAIK my TP-Link TL-WN722N USB dongle uses the ath9k_htc driver, but I haven't found anything relevant in the respective sources ( htc_*.{c, h} ) Apart from that, I suspect that the USB-net driver itself might also introduce some fixed delays which affect the minimum time-spacing measurement that my software can perceive at the receiver side. Here follow the details of my hardware: https://wikidevi.com/wiki/TP-LINK_TL-WN722N I am using linux kernel 3.11 at the moment, but I am flexible to switch to a newer version. Thank you in advance for your help, Dimos -------------- next part -------------- An HTML attachment was scrubbed... URL: http://lists.ath9k.org/pipermail/ath9k-devel/attachments/20140214/aa394a18/attachment.htm