Undesired behavior; mke2fs defaults to reserving 5% of the volume for the root user. 5% of a 2TB volume is 100GB. The rationale for root reservation (syslogd, etc...) does not require 100GB. As volumes get larger, this default makes less and less sense. Proposal; If the user does not specify their preferred reserve_ratio on the command-line (-m), use the less of 5% or MAX_RSRV_SIZE. I propose 10GiB as a sensible maximum default reservation for root. Patch: Follows and http://capsid.brandeis.edu/~elrad/e2fsprog.gitdiff Tested on the latest git+patch, RHEL5 (2.6.18-194.17.1.el5) with a 12TB volume (which would reserve 600GB under the default!): # /root/e2fsprogs/misc/mke2fs -T ext4 -L scratch /dev/sdd1 [...] OS type: Linux Block size=4096 (log=2) Fragment size=4096 (log=2) Stride=0 blocks, Stripe width=0 blocks 732422144 inodes, 2929671159 blocks 2621440 blocks (0.09%) reserved for the super user [...] Oren Elrad Dept. of Physics Brandeis University ---- Patch follows ---- diff --git a/misc/mke2fs.c b/misc/mke2fs.c index 9798b88..0ff3785 100644 --- a/misc/mke2fs.c +++ b/misc/mke2fs.c @@ -108,6 +108,8 @@ profile_t profile; int sys_page_size = 4096; int linux_version_code = 0; +static const unsigned long long MAX_RSRV_SIZE = 10ULL * (1 << 30); // 10 GiB + static void usage(void) { fprintf(stderr, _("Usage: %s [-c|-l filename] [-b block-size] " @@ -1154,7 +1156,7 @@ static void PRS(int argc, char *argv[]) int inode_ratio = 0; int inode_size = 0; unsigned long flex_bg_size = 0; - double reserved_ratio = 5.0; + double reserved_ratio = -1.0; // Default: lesser of 5%, MAX_RSRV_SIZE int lsector_size = 0, psector_size = 0; int show_version_only = 0; unsigned long long num_inodes = 0; /* unsigned long long to catch too-large input */ @@ -1893,9 +1895,17 @@ profile_error: /* * Calculate number of blocks to reserve + * If reserved_ratio >= 0.0, it was passed as an argument, use it as-is + * If reserved_ratio < 0.0, no argument was passed, choose the lesser of 5%, MAX_RSRV_SIZE */ - ext2fs_r_blocks_count_set(&fs_param, reserved_ratio * - ext2fs_blocks_count(&fs_param) / 100.0); + if ( reserved_ratio >= 0.0 ) { + ext2fs_r_blocks_count_set(&fs_param, reserved_ratio * + ext2fs_blocks_count(&fs_param) / 100.0); + } else { + const blk64_t r_blk_count = ext2fs_blocks_count(&fs_param) / 20.0; + const blk64_t max_r_blk_count = MAX_RSRV_SIZE / blocksize; + ext2fs_r_blocks_count_set(&fs_param, (r_blk_count < max_r_blk_count ? r_blk_count : max_r_blk_count)); + } } static int should_do_undo(const char *name) By making a contribution to this project, I certify that: (a) The contribution was created in whole or in part by me and I have the right to submit it under the open source license indicated in the file; (d) I understand and agree that this project and the contribution are public and that a record of the contribution (including all personal information I submit with it, including my sign-off) is maintained indefinitely and may be redistributed consistent with this project or the open source license(s) involved. Signed-off-by: Oren M Elrad <elrad@xxxxxxxxxxxx> -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
