Adding back ceph-devel My point was, ok, ruling out 0, then we can create a block device of size 1 byte. Is that useful? No, it is not. How about 10 bytes? 1000? 1MB? There's no good reason to rule out zero. Is it causing a problem somehow? On 07/23/2015 06:06 PM, zhengbin.08747@xxxxxxx wrote: > If I create a block whose size is zero, it means you absolutely can not use it unless you resize it > > > what arbitrary minimum size is too small? -----> I do not know, If I create a block whose size is larger than zero,it may be can use. > And why do we have to define a minimum size? we can just make sure the block size is larger than zero > > -----邮件原件----- > 发件人: Dan Mick [mailto:dmick@xxxxxxxxxx] > 发送时间: 2015年7月24日 5:25 > 收件人: Jason Dillaman; zhengbin 08747 (RD) > 抄送: ceph-devel > 主题: Re: hello, I am confused about a question of rbd > > Why not zero? > > If the answer is "it can't be used", then, what arbitrary minimum size is too small? > > (also, given that resize exists, it can be used for storage after a resize.) > > On 07/23/2015 06:03 AM, Jason Dillaman wrote: >> According to the git history, support for zero MB images for the create/resize commands was explicitly added by commit 08f47a4. Dan Mick or Josh Durgin could probably better explain the history behind the change since it was before my time. >> > > ------------------------------------------------------------------------------------------------------------------------------------- > 本邮件及其附件含有杭州华三通信技术有限公司的保密信息,仅限于发送给上面地址中列出 > 的个人或群组。禁止任何其他人以任何形式使用(包括但不限于全部或部分地泄露、复制、 > 或散发)本邮件中的信息。如果您错收了本邮件,请您立即电话或邮件通知发件人并删除本 > 邮件! > This e-mail and its attachments contain confidential information from H3C, which is > intended only for the person or entity whose address is listed above. Any use of the > information contained herein in any way (including, but not limited to, total or partial > disclosure, reproduction, or dissemination) by persons other than the intended > recipient(s) is prohibited. If you receive this e-mail in error, please notify the sender > by phone or email immediately and delete it! > -- Dan Mick Red Hat, Inc. Ceph docs: http://ceph.com/docs -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html