search for: fullblock

...ts/test-truncate4.sh > index e4be626b..c5dc608c 100755 > --- a/tests/test-truncate4.sh > +++ b/tests/test-truncate4.sh > -requires qemu-io --version > +requires nbdsh --version > +requires truncate --help We probably don't need truncate... > + > +if ! dd --help | grep fullblock; then > + echo "$0: requires GNU dd with the iflag=fullblock option" > + exit 77 > +fi > > sock=`mktemp -u` > -files="truncate4.out truncate4.pid $sock truncate4.data" > +data=truncate4.data > +files="truncate4.pid $sock $data" >...

This commit works for me, but TBH I'm not clear on what the actual purpose of this test is supposed to be. Rich.

...mnt/syslinux.cfg umount -d mnt losetup -o 11534336 -s 9437184 /dev/loop7 flat mkfs.ext2 -q /dev/loop7 mount -t ext2 /dev/loop7 mnt extlinux -i mnt echo LINUX PARTITION-2 > mnt/extlinux.conf umount -d mnt printf '\002' | cat /usr/share/syslinux/altmbr_c.bin - | dd bs=440 count=1 iflag=fullblock conv=notrunc of=flat qemu-kvm -nodefaults -sdl -m 4M -vga cirrus -drive file=flat,if=virtio,readonly ---------- Note also that iflag=fullblock above is necessary, yet the wiki misses it. -- Maxim Kammerer Libert? Linux (discussion / support: http://dee.su/liberte-contribute)

...0 2016 null crw-rw-rw- 1 1, 5 Jun 15 2015 zero (on cygwin): /h> ll zero null -rwxrw-rw- 1 0 May 20 2016 null* -rw-rw-rw- 1 0 Jun 15 2015 zero For write, I used cygwin's 'dd' with if=/dev/zero and of=/h/null. For read, I used if=/h/zero and of=/dev/null. Flags for reading: iflag=fullblock conv=nocreat and for writing: oflag=direct iflag=fullblock conv=nocreat,notrunc To test the CPU bounding, I just tried limiting the clock speeds on the client and server. Limiting the linux-server's max cpu-speed had the most affect on performance: (limited to 1.6GHz instead of 2.4GHz) (33%...

What is the maximum speed for download from a samba share? I have a 100 kbit/s Internet The maximum speed for a download from my  webserver with samba is about 25.000 kbit/s The bottleneck is the samba access.  Without samba  I can download with 100 kbit/s So the question? is it possible to get more speed or is this the maximum speed with samba? I tried a lot of hints for samba tuning but

...ection state). +# shorter. If the actions of connection B affect the size visible +# through connection A, we didn't isolate per-connection state. source ./functions.sh set -e set -x -requires qemu-io --version +requires nbdsh --version +requires truncate --help + +if ! dd --help | grep fullblock; then + echo "$0: requires GNU dd with the iflag=fullblock option" + exit 77 +fi sock=`mktemp -u` -files="truncate4.out truncate4.pid $sock truncate4.data" +data=truncate4.data +files="truncate4.pid $sock $data" rm -f $files cleanup_fn rm -f $files -# Init...

...e of the block contents which was written to the stick. Neither the MBR parts nor the data dummy. Do you get the same result if you fill the entire stick with block_seq by omitting dd option count=647 ? /home/dpchrist/sandbox/syslinux/thomas-schmitt/block_seq-20170321-0141/block _seq | dd iflag=fullblock bs=1M of=/dev/sdb which will end intentionally by i/o error. And then again dd if=/home/dpchrist/src/syslinux/syslinux-6.03+dfsg+dpchrist/bios/mbr/martins_mbr.bin of=/dev/sdb dd if=/mnt/samba/data/dpchrist/iso/debian/8.7.1/i386/debian-8.7.1-i386-xfce-CD-1.iso bs=1 count=80 skip=432 of=/dev/sd...

...modes in VM settings. The real problem is: when guest writes data in small blocks, host CPU becomes a bottleneck. I hava a relatively old 24-core Xeon. Host `top` shows 130% CPU usage by qemu-kvm, when I run the following command: [root@wc8ws-auth ~]# </dev/zero timeout -sINT 30s dd iflag=fullblock oflag=direct conv=notrunc of=./bigfile bs=8192 140384+0 records in 140384+0 records out 1150025728 bytes (1.2 GB) copied, 29.9992 s, 38.3 MB/s I tried all buses, cache modes and IO modes; "Cache mode=none" is slower, others are almost equal. I moved from image file to LVM. Th...

...l error: exception Guestfs.Handle_closed("disk_format") ... #!/bin/bash set -x img=disk.img sprs=disk.sparse.img kname=vda test -f ${img} && exit 1 test -f ${sprs} && exit 1 find /usr/share/ -type f -print0 | xargs -0 cat | dd bs=$(( 1024 * 1024 )) count=$(( 42 )) iflag=fullblock of=${img} ls -lhsS ${img} time guestfish -v <<_EOF_ add ${img} run part-disk /dev/${kname} mbr blockdev-rereadpt /dev/${kname} mkfs ext2 /dev/${kname}1 blockdev-rereadpt /dev/${kname} mount /dev/${kname}1 / mkdir /y ls / ls /y umount / sync _EOF_ time virt-sparsify -v ${img} ${sprs} ls -lhsS...

...is -at an offset from the base of the device or file. +at an offset from the base of the device or file. Some older versions +did not accept the short format, *-t*. *-z*, *--zipdrive* Assume zipdrive geometry ('--heads 64 --sectors 32'). See also *--head* @@ -195,7 +195,7 @@ iflag=fullblock conv=notrunc of=/dev/sda + Note: using 'cat' for writing the MBR can under some circumstances cause -data loss or overwritting. For this reason, using 'dd' is recommended +data loss or overwriting. For this reason, using 'dd' is recommended for all situations. //[FIX...

...y Arch: syslinux-install_update -i -a -m - manual method with mbr.bin (first setting the boot flag on /dev/sda3): dd if=/usr/lib/syslinux/bios/mbr.bin bs=440 count=1 of=/dev/sda - manual method with altmbr.bin: printf '\x3' | cat /usr/lib/syslinux/bios/altmbr.bin - | dd bs=440 count=1 iflag=fullblock conv=notrunc of=/dev/sda No luck any way. Then I just restored the Microsoft MBR. On 22/01/2014, Gene Cumm <gene.cumm at gmail.com> wrote: > On Tue, Jan 21, 2014 at 7:42 AM, David de Marneffe > <daviddemarneffe at gmail.com> wrote: >> Hello Gene, thanks for your reply. &gt...

Hi, i have uploaded a little gz compressed tarball http://scdbackup.webframe.org/block_seq.tgz containing -rwxr-xr-x thomas/thomas 4552 2017-03-21 09:23 block_seq -rw-r--r-- thomas/thomas 315 2017-03-21 09:22 block_seq.c To be unpacked in a suitable directory by tar xvzf block_seq.tgz The binary "block_seq" was compiled on Debian Jessie. If it does not run, do cc -o

Hello Gene, thanks for your reply. Yes BIOS mode. The config wants a menu, which loads fine under ext4 and not under btrfs. Under btrfs I have also tried to remove the syslinux.cfg file altogether (which should trigger the boot: prompt if I am not mistaken) and the result is the same: only the copyright line appears and no prompt. The three letter sequence is EDD. The disk is 160GB, here is the

...56 c3 00 00 00 00 00 00 00 |<.u.[X]V........| 00000190 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 000001b0 Build the USB stick: 2017-03-21 13:44:13 root at hd-tracy ~ # /home/dpchrist/sandbox/syslinux/thomas-schmitt/block_seq-20170321-0141/block_seq | dd iflag=fullblock bs=1M count=647 of=/dev/sdb 647+0 records in 647+0 records out 678428672 bytes (678 MB) copied, 133.741 s, 5.1 MB/s 2017-03-21 13:47:30 root at hd-tracy ~ # dd if=/dev/sdb count=4 2>/dev/null | hexdump -C 00000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| * 00000200...

...sock(2, 10809)' -c 'print(h.get_size())' 1073741824 $ ./run nbdfuse mp --vsock 2 10809 & $ ll mp/ total 0 -rw-rw-rw-. 1 rjones rjones 1073741824 Oct 18 16:23 nbd $ dd if=/dev/random of=mp/nbd bs=1024 count=100 conv=notrunc,nocreat dd: warning: partial read (84 bytes); suggest iflag=fullblock 0+100 records in 0+100 records out 6851 bytes (6.9 kB, 6.7 KiB) copied, 0.013797 s, 497 kB/s (Performance of FUSE is not great, it should be better using raw libnbd.) I mainly wrote this to show that it can be done. It's unclear if this would be faster or slower than the usual way that NBD d...

...sock(2, 10809)' -c 'print(h.get_size())' 1073741824 $ ./run nbdfuse mp --vsock 2 10809 & $ ll mp/ total 0 -rw-rw-rw-. 1 rjones rjones 1073741824 Oct 18 16:23 nbd $ dd if=/dev/random of=mp/nbd bs=1024 count=100 conv=notrunc,nocreat dd: warning: partial read (84 bytes); suggest iflag=fullblock 0+100 records in 0+100 records out 6851 bytes (6.9 kB, 6.7 KiB) copied, 0.013797 s, 497 kB/s (Performance of FUSE is not great, it should be better using raw libnbd.) I mainly wrote this to show that it can be done. It's unclear if this would be faster or slower than the usual way that NBD d...