From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 763EE4FDA59 for ; Fri, 18 Sep 2026 13:33:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.10 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789738402; cv=none; b=TQHHqNIkj4EEkKFcR+UwcUgEECQ9hGn6+0A5OGZ8D9C4pR9FSW34+8jvA5fhe9qn4TPSOwUMpGzgUJiYPJelcA+V/jp0hJ3PrChpmg4u4LGxCuK9We4GTEMZyJygLlNF4p0UOs6SCCUSJrcajLqVh86nE+LaYDYzekh+eWbGxvI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789738402; c=relaxed/simple; bh=pMriqRWop9RRBaxFqNlEj6k2sISo5ki9t7sSSotR/PM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=as3wPW9U7yNaSF7JSxReGNlr3HIk8PDUzRpJFQ9gqsmKtdLwS26vM1tAJH8UC9cAKzAz0vpdGX7UAbwr9BtlmFgO4ZFoQSiXdeomVRAhhnC7AvA9RqqLteyn69MS+jf9p8o2hNqaZQm0jgaaD9bjw9Cr4qBGGmcLoqllR/K0IqY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=MMNrGRmT; arc=none smtp.client-ip=192.198.163.10 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="MMNrGRmT" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1789738400; x=1821274400; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=pMriqRWop9RRBaxFqNlEj6k2sISo5ki9t7sSSotR/PM=; b=MMNrGRmTUuNFgN960sLGTm78U0sX/tY4Swx0IKHCVLWZ1kgLfkUBJt2O BcmQHo1K+NOCTdMb/ZeHOYtICfehMBjxzN2mvzOn9TVd3ll06/TSN8RMD z+jpxSJ466yZGyeVsMCaxCufdnf+o5gRygYZh/F7rnWShlEgzo6m7wjA0 cSVtxo/vgIg17OBrnHsH4cGxxJzJ3OfZKUzsONsO0pQs3Gz7sw/+0WvoR +8dDsUal5K1sMLJ58vnLRwx085kYxSn51qg4NOHaRSBEYinKJxqrok2Zv ujC3VZAQr7n2w9GHXOv9m2EHRCaCX0qBR2yaIJREAoQLseLPGbaGRMSrk A==; X-CSE-ConnectionGUID: rZqjWbSPQ8+q6DDkrgCl8A== X-CSE-MsgGUID: wEjZ8GeATkuTWIEjC/I2tA== X-IronPort-AV: E=McAfee;i="6800,10657,11908"; a="101592497" X-IronPort-AV: E=Sophos;i="6.27,109,1787036400"; d="scan'208";a="101592497" Received: from fmviesa010.fm.intel.com ([10.60.135.150]) by fmvoesa104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Sep 2026 06:33:20 -0700 X-CSE-ConnectionGUID: UX2ng1vHSlGT0mhMPseRAQ== X-CSE-MsgGUID: Fxz136FOTai9xYvPBAc6RA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,109,1787036400"; d="scan'208";a="270717952" Received: from amlin-019-225.igk.intel.com ([10.102.19.225]) by fmviesa010.fm.intel.com with ESMTP; 18 Sep 2026 06:33:19 -0700 From: Aleksandr Loktionov To: intel-wired-lan@lists.osuosl.org, anthony.l.nguyen@intel.com, aleksandr.loktionov@intel.com Cc: netdev@vger.kernel.org, Simon Horman Subject: [PATCH iwl-next v2 1/4] ixgbe: lower IXGBE_ITR_ADAPTIVE_MAX_USECS to prevent RX starvation Date: Fri, 18 Sep 2026 15:33:13 +0200 Message-ID: <20260918133317.4169815-2-aleksandr.loktionov@intel.com> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260918133317.4169815-1-aleksandr.loktionov@intel.com> References: <20260918133317.4169815-1-aleksandr.loktionov@intel.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Alexander Duyck At the current maximum of 126 us the minimum bulk-mode interrupt rate is ~7936 interrupts/s. Under sustained full-line-rate bulk RX traffic this is low enough that descriptor ring starvation can occur before the next interrupt fires. Lower IXGBE_ITR_ADAPTIVE_MAX_USECS from 126 to 84 us. This raises the minimum rate to ~11905 interrupts/s (~12K ints/s), providing enough headroom to drain the ring before it wraps. Signed-off-by: Alexander Duyck Signed-off-by: Aleksandr Loktionov Reviewed-by: Simon Horman --- drivers/net/ethernet/intel/ixgbe/ixgbe.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe.h b/drivers/net/ethernet/intel/ixgbe/ixgbe.h index 9b82175..1a7fd90 100644 --- a/drivers/net/ethernet/intel/ixgbe/ixgbe.h +++ b/drivers/net/ethernet/intel/ixgbe/ixgbe.h @@ -475,7 +475,7 @@ static inline unsigned int ixgbe_rx_pg_order(struct ixgbe_ring *ring) #define IXGBE_ITR_ADAPTIVE_MIN_INC 2 #define IXGBE_ITR_ADAPTIVE_MIN_USECS 10 -#define IXGBE_ITR_ADAPTIVE_MAX_USECS 126 +#define IXGBE_ITR_ADAPTIVE_MAX_USECS 84 #define IXGBE_ITR_ADAPTIVE_LATENCY 0x80 #define IXGBE_ITR_ADAPTIVE_BULK 0x00 -- 2.52.0