Re: [Freedos-user] Report back: QEMU - Max size of Linux access folder
On Sat, Mar 16, 2024, 3:27 AM hms--- via Freedos-user < freedos-user@lists.sourceforge.net> wrote: > Correction. My apologies. My memory doesn't work all that well these days. > Re. Linux error on boot up. I incorrectly said deleting the files in the > /dev/crash directory fixed the problem. > The correct directory is /var/crash > That makes more sense. Nothing should be writing logs to the /dev directory. But writing to /var is more typical. Although I would have expected /var/log/crash … but I don't know Ubuntu systems very well. > ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] Report back: QEMU - Max size of Linux access folder
Correction. My apologies. My memory doesn't work all that well these days. Re. Linux error on boot up. I incorrectly said deleting the files in the /dev/crash directory fixed the problem. The correct directory is /var/crash On 2024/03/14 13:32, hms--- via Freedos-user wrote: Thanks. I will try writeback=off as well The manual says "The default mode is *cache=writeback*." and further on it says- By default, the cache.writeback=on mode is used. It will report data writes as completed as soon as the data is present in the host page cache. This is safe as long as your guest OS makes sure to correctly flush disk caches where needed. If your guest OS does not handle volatile disk write caches correctly and your host crashes or loses power, then the guest may experience data corruption. For such guests, you should consider using cache.writeback=off. This means that the host page cache will be used to read and write data, but write notification will be sent to the guest only after QEMU has made sure to flush each write to the disk. Be aware that this has a major impact on performance. On 2024/03/14 08:25, Louis Santillan wrote: You might try updating the 2nd drive's argument to `-drive file=fat:rw:dosfiles/,format=raw,cache=writeback`. [0] [0] https://manpages.debian.org/unstable/qemu-system-x86/qemu-system-i386.1.en.html On Wed, Mar 13, 2024 at 10:29 AM h...@iafrica.com wrote: I removed CDROM and Sound support. I moved all program directories from the D: drive (FAT16 access drive) to the C: drive and this appears to have improved the speed to about 7x slower. I then checked to see if KVM was running and it was. The command line I was using to invoke the emulator was:- $ qemu-system-i386 -m 32 -rtc base=localtime -drive file=dos.img,index=0,media=disk,format=raw -drive file=fat:rw:dosfiles/,format=raw -boot order=c -display sdl I then added "-enable-kvm" eg. $ qemu-system-i386 -m 32 -rtc base=localtime -drive file=dos.img,index=0,media=disk,format=raw -drive file=fat:rw:dosfiles/,format=raw -boot order=c -display sdl -enable-kvm This has moved speed to parity to 2x slower which is excellent. I have switched to the 4DOS shell with no speed penalty. In 4DOS I have always used Function key F11 to toggle between two directories. This does not work as QEMU appears to use F11 to toggle between current window size and full screen. I have searched on the Internet but not found any reference to the use off F11 in QEMU. Anyone have any ideas how to reassign the key? I suspect it is hard coded? Using drive D:, the access drive, appears to be problematic. Best not to use it other than transfer files. On 2024/03/13 18:53, Louis Santillan wrote: What was the qemu command you used? It sounds like you paying a double penalty somewhere for how you’re get the disk image into qemu. Loopback devices pay some penalty. 10x seems like some option is missing to improve performance. On Wed, Mar 13, 2024 at 2:57 AM hms--- via Freedos-user wrote: Hi All Some feedback. Creating a 2G image allowed me to assemble source code correctly. The only penalty being speed. About 6 to 11 times slower than running DOS under XP. I mounted the image and copied source files from backup directory to mounted C: drive. Lubuntu Linux error on boot up resolved. QEMU-KVM had crashed on two occasions and logs created in the /dev/crash directory. Deleting the log files in /dev/crash removed the error message on start up. I used "mount" instead of "guestmount". Steps below. Display start sector and sector size: $ fdisk -l dos.img Eg. 63 and 512 bytes. Offset = 63 * 512 = 32256 Create directory: $ mkdir /tmp/dos Mount image in directory: $ sudo mount -o loop,offset=32256 dos.img /tmp/dos Copy directories: Eg. $ cp -r /temp/source-dir /tmp/dos Unmount image: umount /tmp/dos John ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] Report back: QEMU - Max size of Linux access folder
Thanks. I will try writeback=off as well The manual says "The default mode is *cache=writeback*." and further on it says- By default, the cache.writeback=on mode is used. It will report data writes as completed as soon as the data is present in the host page cache. This is safe as long as your guest OS makes sure to correctly flush disk caches where needed. If your guest OS does not handle volatile disk write caches correctly and your host crashes or loses power, then the guest may experience data corruption. For such guests, you should consider using cache.writeback=off. This means that the host page cache will be used to read and write data, but write notification will be sent to the guest only after QEMU has made sure to flush each write to the disk. Be aware that this has a major impact on performance. On 2024/03/14 08:25, Louis Santillan wrote: You might try updating the 2nd drive's argument to `-drive file=fat:rw:dosfiles/,format=raw,cache=writeback`. [0] [0] https://manpages.debian.org/unstable/qemu-system-x86/qemu-system-i386.1.en.html On Wed, Mar 13, 2024 at 10:29 AM h...@iafrica.com wrote: I removed CDROM and Sound support. I moved all program directories from the D: drive (FAT16 access drive) to the C: drive and this appears to have improved the speed to about 7x slower. I then checked to see if KVM was running and it was. The command line I was using to invoke the emulator was:- $ qemu-system-i386 -m 32 -rtc base=localtime -drive file=dos.img,index=0,media=disk,format=raw -drive file=fat:rw:dosfiles/,format=raw -boot order=c -display sdl I then added "-enable-kvm" eg. $ qemu-system-i386 -m 32 -rtc base=localtime -drive file=dos.img,index=0,media=disk,format=raw -drive file=fat:rw:dosfiles/,format=raw -boot order=c -display sdl -enable-kvm This has moved speed to parity to 2x slower which is excellent. I have switched to the 4DOS shell with no speed penalty. In 4DOS I have always used Function key F11 to toggle between two directories. This does not work as QEMU appears to use F11 to toggle between current window size and full screen. I have searched on the Internet but not found any reference to the use off F11 in QEMU. Anyone have any ideas how to reassign the key? I suspect it is hard coded? Using drive D:, the access drive, appears to be problematic. Best not to use it other than transfer files. On 2024/03/13 18:53, Louis Santillan wrote: What was the qemu command you used? It sounds like you paying a double penalty somewhere for how you’re get the disk image into qemu. Loopback devices pay some penalty. 10x seems like some option is missing to improve performance. On Wed, Mar 13, 2024 at 2:57 AM hms--- via Freedos-user wrote: Hi All Some feedback. Creating a 2G image allowed me to assemble source code correctly. The only penalty being speed. About 6 to 11 times slower than running DOS under XP. I mounted the image and copied source files from backup directory to mounted C: drive. Lubuntu Linux error on boot up resolved. QEMU-KVM had crashed on two occasions and logs created in the /dev/crash directory. Deleting the log files in /dev/crash removed the error message on start up. I used "mount" instead of "guestmount". Steps below. Display start sector and sector size: $ fdisk -l dos.img Eg. 63 and 512 bytes. Offset = 63 * 512 = 32256 Create directory: $ mkdir /tmp/dos Mount image in directory: $ sudo mount -o loop,offset=32256 dos.img /tmp/dos Copy directories: Eg. $ cp -r /temp/source-dir /tmp/dos Unmount image: umount /tmp/dos John ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] Report back: QEMU - Max size of Linux access folder
You might try updating the 2nd drive's argument to `-drive file=fat:rw:dosfiles/,format=raw,cache=writeback`. [0] [0] https://manpages.debian.org/unstable/qemu-system-x86/qemu-system-i386.1.en.html On Wed, Mar 13, 2024 at 10:29 AM h...@iafrica.com wrote: > I removed CDROM and Sound support. I moved all program directories from > the D: drive (FAT16 access drive) to the C: drive and this appears to have > improved the speed to about 7x slower. I then checked to see if KVM was > running and it was. > The command line I was using to invoke the emulator was:- > $ qemu-system-i386 -m 32 -rtc base=localtime -drive > file=dos.img,index=0,media=disk,format=raw -drive > file=fat:rw:dosfiles/,format=raw -boot order=c -display sdl > I then added "-enable-kvm" > eg. > $ qemu-system-i386 -m 32 -rtc base=localtime -drive > file=dos.img,index=0,media=disk,format=raw -drive > file=fat:rw:dosfiles/,format=raw -boot order=c -display sdl -enable-kvm > This has moved speed to parity to 2x slower which is excellent. > > I have switched to the 4DOS shell with no speed penalty. In 4DOS I have > always used Function key F11 to toggle between two directories. This does > not work as QEMU appears to use F11 to toggle between current window size > and full screen. I have searched on the Internet but not found any > reference to the use off F11 in QEMU. Anyone have any ideas how to reassign > the key? I suspect it is hard coded? > > Using drive D:, the access drive, appears to be problematic. Best not to > use it other than transfer files. > > > On 2024/03/13 18:53, Louis Santillan wrote: > > What was the qemu command you used? It sounds like you paying a double > penalty somewhere for how you’re get the disk image into qemu. Loopback > devices pay some penalty. 10x seems like some option is missing to improve > performance. > > On Wed, Mar 13, 2024 at 2:57 AM hms--- via Freedos-user < > freedos-user@lists.sourceforge.net> wrote: > >> Hi All >> Some feedback. Creating a 2G image allowed me to assemble source code >> correctly. The only penalty being speed. About 6 to 11 times slower than >> running DOS under XP. >> I mounted the image and copied source files from backup directory to >> mounted C: drive. >> Lubuntu Linux error on boot up resolved. QEMU-KVM had crashed on two >> occasions and logs created in the /dev/crash directory. Deleting the log >> files in /dev/crash removed the error message on start up. >> >> I used "mount" instead of "guestmount". Steps below. >> >> Display start sector and sector size: >> $ fdisk -l dos.img >> Eg. 63 and 512 bytes. Offset = 63 * 512 = 32256 >> >> Create directory: >> $ mkdir /tmp/dos >> >> Mount image in directory: >> $ sudo mount -o loop,offset=32256 dos.img /tmp/dos >> >> Copy directories: >> Eg. >> $ cp -r /temp/source-dir /tmp/dos >> >> Unmount image: >> umount /tmp/dos >> >> John >> >> >> ___ >> Freedos-user mailing list >> Freedos-user@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/freedos-user >> > > ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] Report back: QEMU - Max size of Linux access folder
I removed CDROM and Sound support. I moved all program directories from the D: drive (FAT16 access drive) to the C: drive and this appears to have improved the speed to about 7x slower. I then checked to see if KVM was running and it was. The command line I was using to invoke the emulator was:- $ qemu-system-i386 -m 32 -rtc base=localtime -drive file=dos.img,index=0,media=disk,format=raw -drive file=fat:rw:dosfiles/,format=raw -boot order=c -display sdl I then added "-enable-kvm" eg. $ qemu-system-i386 -m 32 -rtc base=localtime -drive file=dos.img,index=0,media=disk,format=raw -drive file=fat:rw:dosfiles/,format=raw -boot order=c -display sdl -enable-kvm This has moved speed to parity to 2x slower which is excellent. I have switched to the 4DOS shell with no speed penalty. In 4DOS I have always used Function key F11 to toggle between two directories. This does not work as QEMU appears to use F11 to toggle between current window size and full screen. I have searched on the Internet but not found any reference to the use off F11 in QEMU. Anyone have any ideas how to reassign the key? I suspect it is hard coded? Using drive D:, the access drive, appears to be problematic. Best not to use it other than transfer files. On 2024/03/13 18:53, Louis Santillan wrote: What was the qemu command you used? It sounds like you paying a double penalty somewhere for how you’re get the disk image into qemu. Loopback devices pay some penalty. 10x seems like some option is missing to improve performance. On Wed, Mar 13, 2024 at 2:57 AM hms--- via Freedos-user wrote: Hi All Some feedback. Creating a 2G image allowed me to assemble source code correctly. The only penalty being speed. About 6 to 11 times slower than running DOS under XP. I mounted the image and copied source files from backup directory to mounted C: drive. Lubuntu Linux error on boot up resolved. QEMU-KVM had crashed on two occasions and logs created in the /dev/crash directory. Deleting the log files in /dev/crash removed the error message on start up. I used "mount" instead of "guestmount". Steps below. Display start sector and sector size: $ fdisk -l dos.img Eg. 63 and 512 bytes. Offset = 63 * 512 = 32256 Create directory: $ mkdir /tmp/dos Mount image in directory: $ sudo mount -o loop,offset=32256 dos.img /tmp/dos Copy directories: Eg. $ cp -r /temp/source-dir /tmp/dos Unmount image: umount /tmp/dos John ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
Re: [Freedos-user] Report back: QEMU - Max size of Linux access folder
What was the qemu command you used? It sounds like you paying a double penalty somewhere for how you’re get the disk image into qemu. Loopback devices pay some penalty. 10x seems like some option is missing to improve performance. On Wed, Mar 13, 2024 at 2:57 AM hms--- via Freedos-user < freedos-user@lists.sourceforge.net> wrote: > Hi All > Some feedback. Creating a 2G image allowed me to assemble source code > correctly. The only penalty being speed. About 6 to 11 times slower than > running DOS under XP. > I mounted the image and copied source files from backup directory to > mounted C: drive. > Lubuntu Linux error on boot up resolved. QEMU-KVM had crashed on two > occasions and logs created in the /dev/crash directory. Deleting the log > files in /dev/crash removed the error message on start up. > > I used "mount" instead of "guestmount". Steps below. > > Display start sector and sector size: > $ fdisk -l dos.img > Eg. 63 and 512 bytes. Offset = 63 * 512 = 32256 > > Create directory: > $ mkdir /tmp/dos > > Mount image in directory: > $ sudo mount -o loop,offset=32256 dos.img /tmp/dos > > Copy directories: > Eg. > $ cp -r /temp/source-dir /tmp/dos > > Unmount image: > umount /tmp/dos > > John > > > ___ > Freedos-user mailing list > Freedos-user@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/freedos-user > ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
[Freedos-user] Report back: QEMU - Max size of Linux access folder
Hi All Some feedback. Creating a 2G image allowed me to assemble source code correctly. The only penalty being speed. About 6 to 11 times slower than running DOS under XP. I mounted the image and copied source files from backup directory to mounted C: drive. Lubuntu Linux error on boot up resolved. QEMU-KVM had crashed on two occasions and logs created in the /dev/crash directory. Deleting the log files in /dev/crash removed the error message on start up. I used "mount" instead of "guestmount". Steps below. Display start sector and sector size: $ fdisk -l dos.img Eg. 63 and 512 bytes. Offset = 63 * 512 = 32256 Create directory: $ mkdir /tmp/dos Mount image in directory: $ sudo mount -o loop,offset=32256 dos.img /tmp/dos Copy directories: Eg. $ cp -r /temp/source-dir /tmp/dos Unmount image: umount /tmp/dos John ___ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
