From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.14]) (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 D38793BB13F for ; Tue, 15 Sep 2026 12:55:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.14 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789476943; cv=none; b=OqMOkDNX1jIboltdm5vTTAuQfNe55Y30N0jAifp509I6Clxkl6MyA5Wpc9SQVxKGq/vwuEpadmKA82gOklRxqxtRXouTg8epafoXk7/D2ubJeEZ81enGgMpCj/wEksHDCfVaSv9Ck8BsBHeloYKt/AkAVwrrs0wI71XPA1IQM9I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789476943; c=relaxed/simple; bh=tDUir5n0cojiGdZCBkMQYJ8ICGb6dImsb7j6dxNI/D0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=UpSlvxdACUvJsfjY7ZtrXEpV2/cHAAMlDdixL7CuwCcAZaW3vm8LtHVry3hNQAZg+MwKtQ8ibBzP9RtFb4C+NdCYafukjZDakX26d5M9O2XYMa5AkDUNDim7zQrNEfePPN2H9b3gdlYhIq/wcG+VfNYPRzKS02JtXk0Yu+IRJT0= 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=nn97w85M; arc=none smtp.client-ip=192.198.163.14 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="nn97w85M" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1789476942; x=1821012942; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=tDUir5n0cojiGdZCBkMQYJ8ICGb6dImsb7j6dxNI/D0=; b=nn97w85MWtt2DQ916OEGlebiM8d3SUzS7XlHiaJcrAGrafg3f10nWN+Z v2TIb0sbTLmtcCte+NT5UBP74BSeBueU3SAUdb8Y02oLgqEg4k8oEHxEO 5JZDVECaCwj3yh6R4qesUoxxvJflgEwgfNonueLdYO/pRvOFJsC9Atxwn dtOSXY/kvTXj/u8iJZxWdsicF7W7vMc44vHko+AhA3wuJ49NhSW6r6AVs 30QgXerOAeJjxL3KIVPaXfvbvKhwT/zurjVNyYgTbkps3LCAKnY+nrsuH KIblmRZmuL0oCyGeFHWQ7ipkd6qMRAFrEoPwrkc4CjpV0GyDb1ZaWdbyC g==; X-CSE-ConnectionGUID: EylHyN3sR+uTOjQF1uqrjw== X-CSE-MsgGUID: Qc3Cm3CgQoO2Ko5e40RZrg== X-IronPort-AV: E=McAfee;i="6800,10657,11905"; a="89853120" X-IronPort-AV: E=Sophos;i="6.27,103,1787036400"; d="scan'208";a="89853120" Received: from fmviesa011.fm.intel.com ([10.60.135.151]) by fmvoesa108.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Sep 2026 05:55:41 -0700 X-CSE-ConnectionGUID: OGFKUvL1SQSpw76CizHwOQ== X-CSE-MsgGUID: SwFl9AVURzmVCXXWXfs6kw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.27,103,1787036400"; d="scan'208";a="1225220" Received: from amlin-019-225.igk.intel.com ([10.102.19.225]) by fmviesa011.fm.intel.com with ESMTP; 15 Sep 2026 05:55:41 -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 Subject: [PATCH iwl-next 1/4] ixgbe: lower IXGBE_ITR_ADAPTIVE_MAX_USECS to prevent RX starvation Date: Tue, 15 Sep 2026 14:55:35 +0200 Message-ID: <20260915125538.3975870-2-aleksandr.loktionov@intel.com> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260915125538.3975870-1-aleksandr.loktionov@intel.com> References: <20260915125538.3975870-1-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 --- 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