From nobody Sun Jul 26 01:01:12 2026 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4h73MF6JKfz6mQR2 for ; Sun, 26 Jul 2026 01:01:13 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "YR1" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4h73MF1zPpz3Lbm for ; Sun, 26 Jul 2026 01:01:13 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1785027673; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=NDhU27i/hQjDBD1wrn6qUkaO+LIvMICdvV+SaYldYPg=; b=d3vJRzRab+nFfDHa0P1mcMUsevDzxATlL5mr0Y5UIZhHTXSLUyChl5RbYDyGcNDAvnG1kF r9PzdFljYUJRtVZsSvKE4RNVQ/5N6kXr0utVA/INcFks8tmyku8mlHcoIBG9RLElMpu0TQ XKNdCIc/ZkPYqVBmkhTIk0+qbaWxlWC/Wg5glmYit5J6H+TadSKJLp896FKkZlJxzTaEvw fl9+zk+ZNJ6gdlEJurW+NrTlAXRF5yixaKEO7lMMO0xVp5gMa6QXvIzg12VY10Gv8/BtUj Bt0Ilr45SBD4PmjbTPz1r5kjRz7akT6OIURaaV0FSrUhcQkfEKivhV342KzJLw== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1785027673; a=rsa-sha256; cv=none; b=Qv27HgPAvcBnBf/UlCQEgoHkxiInMI+jrgKlRgYUSC6gW9z4M8tMQx1em3iO7TMvwu/I5g mV4iZAHqa+77TbQpas8CVhNGQslNISdEjUV9F18NTtKl6B4PLEJdlmR2MfxQNoxf7orWr6 MQyq2v7iQW+5D6iQr5VDO1au4ERcscsjUzmawa1vi+Ed5fQkoK0QHwF7DbNkRA5ddzqytN XcKVdNm1rl5TA0rElPuZTvhsvGxMedq56L/MfOngkhjatUxYmC//Ff4ksYywx2Ujqk25mQ +p+RLfudosTHhKTrhwTGu6sezmWG69fTIy4dhb0ov1qflirUz1qXvnWwo/fz5w== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1785027673; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=NDhU27i/hQjDBD1wrn6qUkaO+LIvMICdvV+SaYldYPg=; b=HJenNTlFo1JiD+3Z0qcXPSGhEW10JpycUpAHqJmPnJN10uWZHLecd4DOSUT1pYkUDFp65f bQz/ILfduxsEQQ6ixPt5Gil8ruXwtCubv3XY00GWnfHs8qGT0jhZSXJZoKPY0DwT2h8vwX mx+gsm461agRO14OwTvaSMakKUgIO3clXvRb8Zn1fL3BZzpiMtB90WmsnYcFiF94aYXbjv dWCSFosr4UIeKgUcRMZDdWu7eSq2oFdBXViVRh6RuEd7HGfwL+OEK5vf7GqjMqhTW+WbMy OVH+t28oOPhjXlr/pVqTOmMqm0cKz+Ec0aTviJJv9wCeoyR+ZDbyiqMX3/pWYA== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) by mxrelay.nyi.freebsd.org (Postfix) with ESMTP id 4h73MD71wdz10b4 for ; Sun, 26 Jul 2026 01:01:12 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from git (uid 1279) (envelope-from git@FreeBSD.org) id 31bc0 by gitrepo.freebsd.org (DragonFly Mail Agent v0.13+ on gitrepo.freebsd.org); Sun, 26 Jul 2026 01:01:12 +0000 To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Kevin Bowling Subject: git: b6b379b94781 - main - em(4): document adaptive interrupt moderation List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-all@freebsd.org Sender: owner-dev-commits-src-all@FreeBSD.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: kbowling X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: b6b379b94781da5d4328f6f57273fbe7bd9dc687 Auto-Submitted: auto-generated Date: Sun, 26 Jul 2026 01:01:12 +0000 Message-Id: <6a655c58.31bc0.232cf28f@gitrepo.freebsd.org> The branch main has been updated by kbowling: URL: https://cgit.FreeBSD.org/src/commit/?id=b6b379b94781da5d4328f6f57273fbe7bd9dc687 commit b6b379b94781da5d4328f6f57273fbe7bd9dc687 Author: Kevin Bowling AuthorDate: 2026-07-25 22:09:48 +0000 Commit: Kevin Bowling CommitDate: 2026-07-26 01:00:02 +0000 em(4): document adaptive interrupt moderation Describe the disabled, adaptive, and low-latency settings and their interrupt-rate tradeoffs. MFC after: 1 week --- share/man/man4/em.4 | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/share/man/man4/em.4 b/share/man/man4/em.4 index 0e9c08560545..4835d41320b2 100644 --- a/share/man/man4/em.4 +++ b/share/man/man4/em.4 @@ -272,6 +272,20 @@ interrupt is generated. .It Va hw.em.max_interrupt_rate Maximum interrupts per second. The default value is 8000. +This is the rate used when adaptive interrupt moderation is disabled, and +the fallback when it has no usable measurement. +.It Va hw.em.enable_aim +Adaptive interrupt moderation. +The interrupt rate is derived from the average size of the packets seen +since the previous interrupt, so that bulk traffic is coalesced while small +packet traffic keeps its latency. +A value of 0 disables it and pins the rate to +.Va hw.em.max_interrupt_rate , +1 selects the normal range, and 2 selects the low-latency range. +The default value is 1. +Setting 2 raises the interrupt rate substantially on small packet workloads +and is rarely a win; prefer the default unless latency has been measured to +matter more than the additional interrupt load. .It Va hw.em.rx_process_limit Maximum number of received packets to process at a time, -1 means unlimited. The default value is 100.