Hello, I have a configuration where I use qemu/qcow loop filesystems on top a nilfs filesystem to yield writeable snapshots. The symptom I see is the nilfs filesystem "ballooning" in size when writing large chunks of data to the qcow loop filesystem. I also see _many_ nilfs checkpoints with small "NBLKINC" counts (>20 <50). My working theory is nilfs creates checkpoints for each synchronous write, and qcow insists on writing synchronously, thus the ballooning of checkpoints. One question is would it be possible to have nilfs not checkpoint so often. I've tried the 'nilfs-tune -i ..' to no avail - apparently synchronous writes overrule this setting. Thanks in advance, Mark T. Confidentiality Notice: The information contained in this electronic e-mail and any accompanying attachment(s) is intended only for the use of the intended recipient and is confidential and/or privileged. If you and we have a confidentiality agreement or other non-disclosure obligations between us, this Notice shall be deemed to mark and identify the content of this email and any attachments as confidential and proprietary. If any reader of this communication is not the intended recipient, unauthorized use, disclosure or copying is strictly prohibited, and may be unlawful. If you have received this communication in error, please immediately notify the sender by return e-mail, and delete the original message and all copies from your system. Thank you. IRS Circular 230 Disclosure: To ensure compliance with requirements imposed by the IRS, please be advised that any U.S. federal tax advice contained in this communication (including any attachments) is not intended or written to be used or relied upon, and cannot be used or relied upon, for the purpose of (i) avoiding penalties under the Internal Revenue Code, or (ii) promoting, marketing or recommending to another party any transaction or matter addressed herein. E-mail is susceptible to data corruption, interception, unauthorized amendment, tampering and viruses, and we only send and receive e-mails on the basis that we are not liable for any such corruption, interception, amendment, tampering or viruses or any consequences thereof. -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html