From mboxrd@z Thu Jan 1 00:00:00 1970 From: Al Viro Subject: Re: io_pgetevents & aio fsync V2 Date: Fri, 6 Apr 2018 04:16:30 +0100 Message-ID: <20180406031630.GU30522@ZenIV.linux.org.uk> References: <20180328072639.16885-1-hch@lst.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20180328072639.16885-1-hch@lst.de> Sender: owner-linux-aio@kvack.org To: Christoph Hellwig Cc: Avi Kivity , linux-aio@kvack.org, linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-api@vger.kernel.org On Wed, Mar 28, 2018 at 09:26:33AM +0200, Christoph Hellwig wrote: > Hi all, > > this patch adds workqueue based fsync offload. Version of this > patch have been floating around for a couple years, but we now > have a user with seastar used by ScyllaDB (who sponsored this > work) that really wants this in addition to the aio poll support. > More details are in the patch itself. > > Because the iocb types have been defined sine day one (and probably > were supported by RHEL3) libaio already supports these calls as-is. > > This also pulls in the aio cleanups and io_pgetevents support previously > submitted and review as part of the aio poll series. The aio poll > series will be resubmitted on top of this series BTW, this is only tangentially related, but... does *anything* call io_submit() for huge amounts of iocb? Check in do_io_submit() is insane - "no more than MAX_LONG total of _pointers_". Compat variant goes for "no more than a page worth of pointers" and there's a hard limit in ioctx_alloc() - we can't ever get more than 8M slots in ring buffer... -- To unsubscribe, send a message with 'unsubscribe linux-aio' in the body to majordomo@kvack.org. For more info on Linux AIO, see: http://www.kvack.org/aio/ Don't email: aart@kvack.org