From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:22243 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1730608AbgEERCn (ORCPT ); Tue, 5 May 2020 13:02:43 -0400 Received: by mail-wr1-f72.google.com with SMTP id g7so1515123wrw.18 for ; Tue, 05 May 2020 10:02:37 -0700 (PDT) Subject: Re: [PATCH v2 0/5] Statsfs: a new ram-based file sytem for Linux kernel statistics References: <20200504110344.17560-1-eesposit@redhat.com> From: Paolo Bonzini Message-ID: <1d12f846-bf89-7b0a-5c71-e61d83b1a36f@redhat.com> Date: Tue, 5 May 2020 19:02:34 +0200 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-s390-owner@vger.kernel.org List-ID: To: Jim Mattson , Emanuele Giuseppe Esposito Cc: David Rientjes , Jonathan Adams , kvm list , Christian Borntraeger , David Hildenbrand , Cornelia Huck , Vitaly Kuznetsov , Alexander Viro , Emanuele Giuseppe Esposito , LKML , linux-mips@vger.kernel.org, kvm-ppc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, Linux FS Devel On 05/05/20 18:53, Jim Mattson wrote: >>> Since this is becoming a generic API (good!!), maybe we can discuss >>> possible ways to optimize gathering of stats in mass? >> Sure, the idea of a binary format was considered from the beginning in >> [1], and it can be done either together with the current filesystem, or >> as a replacement via different mount options. > > ASCII stats are not scalable. A binary format is definitely the way to go. I am totally in favor of having a binary format, but it should be introduced as a separate series on top of this one---and preferably by someone who has already put some thought into the problem (which Emanuele and I have not, beyond ensuring that the statsfs concept and API is flexible enough). ASCII stats are necessary for quick userspace consumption and for backwards compatibility with KVM debugfs (which is not an ABI, but it's damn useful and should not be dropped without providing something as handy), so this is what this series starts from. Paolo