From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-11.1 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1B49DC5517A for ; Mon, 9 Nov 2020 18:48:12 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 71D21206D8 for ; Mon, 9 Nov 2020 18:48:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="G+AG3Hrk" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 71D21206D8 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:54362 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kcCD4-0006Oh-B2 for qemu-devel@archiver.kernel.org; Mon, 09 Nov 2020 13:48:10 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:56398) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kcCCL-0005Xp-PY for qemu-devel@nongnu.org; Mon, 09 Nov 2020 13:47:25 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:26970) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kcCCJ-0002OK-Vw for qemu-devel@nongnu.org; Mon, 09 Nov 2020 13:47:25 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1604947643; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=y53DXKhAw/ZG576P24xIAl7ARW+1l9mWQOTbhLfibms=; b=G+AG3Hrkmr2/jYDCx0c2lTQG0TGU7uUxz0sT58YCvAuMxv+B4tfEZpUZbpM/I4KdmlcKva qpGlN8XEHfCAonfX4JibY1EVgFmVW2jpehD0STDAa1MMNE/YdEcBFBiPdeHv6bXVABi/3A jalQMx3lNoGi66k+Oiprr0PtuJBWxaM= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-98-bLQ3wztfOr-v7G8_c5_WlQ-1; Mon, 09 Nov 2020 13:47:21 -0500 X-MC-Unique: bLQ3wztfOr-v7G8_c5_WlQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 25DE8186DD40; Mon, 9 Nov 2020 18:47:20 +0000 (UTC) Received: from work-vm (ovpn-114-198.ams2.redhat.com [10.36.114.198]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C3C3D5C5FD; Mon, 9 Nov 2020 18:47:08 +0000 (UTC) Date: Mon, 9 Nov 2020 18:47:06 +0000 From: "Dr. David Alan Gilbert" To: Vivek Goyal Subject: Re: [PATCH V2] virtiofsd: Use --thread-pool-size=0 to mean no thread pool Message-ID: <20201109184706.GP3024@work-vm> References: <20201109143548.GA1479853@redhat.com> MIME-Version: 1.0 In-Reply-To: <20201109143548.GA1479853@redhat.com> User-Agent: Mutt/1.14.6 (2020-07-11) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dgilbert@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Received-SPF: pass client-ip=63.128.21.124; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/11/09 01:25:23 X-ACL-Warn: Detected OS = Linux 2.2.x-3.x [generic] [fuzzy] X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: virtio-fs-list , jose.carlos.venegas.munoz@intel.com, qemu-devel@nongnu.org, Stefan Hajnoczi Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Vivek Goyal (vgoyal@redhat.com) wrote: > Right now we create a thread pool and main thread hands over the request > to thread in thread pool to process. Number of threads in thread pool > can be managed by option --thread-pool-size. > > In tests we have noted that many of the workloads are getting better > performance if we don't use a thread pool at all and process all > the requests in the context of a thread receiving the request. > > Hence give user an option to be able to run virtiofsd without using > a thread pool. > > To implement this, I have used existing option --thread-pool-size. This > option defines how many maximum threads can be in the thread pool. > Thread pool size zero freezes thead pool. I can't see why will one > start virtiofsd with a frozen thread pool (hence frozen file system). > So I am redefining --thread-pool-size=0 to mean, don't use a thread pool. > Instead process the request in the context of thread receiving request > from the queue. > > Signed-off-by: Vivek Goyal Reviewed-by: Dr. David Alan Gilbert > --- > tools/virtiofsd/fuse_virtio.c | 36 ++++++++++++++++++++++++++--------- > 1 file changed, 27 insertions(+), 9 deletions(-) > > diff --git a/tools/virtiofsd/fuse_virtio.c b/tools/virtiofsd/fuse_virtio.c > index 83ba07c6cd..944b9a577c 100644 > --- a/tools/virtiofsd/fuse_virtio.c > +++ b/tools/virtiofsd/fuse_virtio.c > @@ -588,13 +588,18 @@ static void *fv_queue_thread(void *opaque) > struct VuDev *dev = &qi->virtio_dev->dev; > struct VuVirtq *q = vu_get_queue(dev, qi->qidx); > struct fuse_session *se = qi->virtio_dev->se; > - GThreadPool *pool; > - > - pool = g_thread_pool_new(fv_queue_worker, qi, se->thread_pool_size, FALSE, > - NULL); > - if (!pool) { > - fuse_log(FUSE_LOG_ERR, "%s: g_thread_pool_new failed\n", __func__); > - return NULL; > + GThreadPool *pool = NULL; > + GList *req_list = NULL; > + > + if (se->thread_pool_size) { > + fuse_log(FUSE_LOG_DEBUG, "%s: Creating thread pool for Queue %d\n", > + __func__, qi->qidx); > + pool = g_thread_pool_new(fv_queue_worker, qi, se->thread_pool_size, > + FALSE, NULL); > + if (!pool) { > + fuse_log(FUSE_LOG_ERR, "%s: g_thread_pool_new failed\n", __func__); > + return NULL; > + } > } > > fuse_log(FUSE_LOG_INFO, "%s: Start for queue %d kick_fd %d\n", __func__, > @@ -669,14 +674,27 @@ static void *fv_queue_thread(void *opaque) > > req->reply_sent = false; > > - g_thread_pool_push(pool, req, NULL); > + if (!se->thread_pool_size) { > + req_list = g_list_prepend(req_list, req); > + } else { > + g_thread_pool_push(pool, req, NULL); > + } > } > > pthread_mutex_unlock(&qi->vq_lock); > pthread_rwlock_unlock(&qi->virtio_dev->vu_dispatch_rwlock); > + > + /* Process all the requests. */ > + if (!se->thread_pool_size && req_list != NULL) { > + g_list_foreach(req_list, fv_queue_worker, qi); > + g_list_free(req_list); > + req_list = NULL; > + } > } > > - g_thread_pool_free(pool, FALSE, TRUE); > + if (pool) { > + g_thread_pool_free(pool, FALSE, TRUE); > + } > > return NULL; > } > -- > 2.25.4 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK