Hello, I saw an old note on kernel mailing list related to the possibility to create ext2/etx3/ext4 file systems with block size larger than 4k. http://lkml.org/lkml/2006/9/8/4 So the limit is block size <= page size, therefore on x86_64 systems the default being 4K for page size, I assumed you have to enable huge pages. But it seems that on both fedora 11 and rhel 5.3 x86_64 you are able to create the file system with an 8Kb block size (with warning), but then you are not able to mount it... So what is the current situation? is this limited because of the x86_64 arch so that instead on Itanium I would be able to do so? Man page for mkfs.ext3 on both rhel and fedora says nothing about page size and tells about 4k being the max... is this correct or does it need to be updated (eventually for itanium or other platforms)? Thanks, Gianluca [root@orastud1 ~]# sysctl -a|grep huge vm.hugetlb_shm_group = 2000 vm.nr_hugepages = 4000 [root@orastud1 ~]# lvcreate -n test_lv -L 2G VolGroup00 [root@orastud1 ~]# mkfs -t ext3 -b 8192 /dev/VolGroup00/test_lv Warning: blocksize 8192 not usable on most systems. mke2fs 1.39 (29-May-2006) mkfs.ext3: 8192-byte blocks too big for system (max 4096) Proceed anyway? (y,n) y Warning: 8192-byte blocks too big for system (max 4096), forced to continue Warning: some 2.4 kernels do not support blocksizes greater than 4096 using ext3. Use -b 4096 if this is an issue for you. warning: 32 blocks unused. Filesystem label= OS type: Linux Block size=8192 (log=3) Fragment size=8192 (log=3) 261888 inodes, 262112 blocks 13107 blocks (5.00%) reserved for the super user First data block=0 Maximum filesystem blocks=268402688 4 block groups 65528 blocks per group, 65528 fragments per group 65472 inodes per group Superblock backups stored on blocks: 65528, 196584 Writing inode tables: done Creating journal (4096 blocks): done Writing superblocks and filesystem accounting information: done This filesystem will be automatically checked every 29 mounts or 180 days, whichever comes first. Use tune2fs -c or -i to override. [root@orastud1 ~]# tune2fs -l /dev/VolGroup00/test_lv |grep "Block size" Block size: 8192 [root@orastud1 ~]# mount /dev/VolGroup00/test_lv /mnt1/ mount: wrong fs type, bad option, bad superblock on /dev/VolGroup00/test_lv, missing codepage or other error In some cases useful info is found in syslog - try dmesg | tail or so dmesg gives, when I try to mount: EXT3-fs: Unsupported filesystem blocksize 8192 on dm-16. The same is on ext4 where instead I get in dmesg: EXT4-fs: bad block size 8192. -- fedora-test-list mailing list fedora-test-list@xxxxxxxxxx To unsubscribe: https://www.redhat.com/mailman/listinfo/fedora-test-list
