582#,http://bbs.wuyou.net/forum.php?mod=redirect&goto=findpost&ptid=417233&pid=4205481&fromuid=298214
If there is no fragment in the file, you can add -l parameter and convert it into blocklist format to speed up reading. If the file is fragmented, it may or may not work.
wintoflash
I personally measured the parameter -l, and the 7gb vhd was loaded into memory. The results are as follows:
1. Put sx70211.vhd on sata ssd, and there is no fragment.
It takes 1 minute and 23 seconds from 0 to 100% without -l parameter.
menuentry "SX70211.vhd-svbus" "/VHD/SX70211.vhd" {
efiload /EFI/grub/ntfs_x64.efi
search --no-floppy --set --file $2
map --mem --rt $2
}
With the -l parameter, it takes 23 seconds.
menuentry "SX70211.vhd-svbus-l" "/VHD/SX70211.vhd" {
efiload /EFI/grub/ntfs_x64.efi
search --no-floppy --set --file $2
map --mem --rt -l $2
}
2、 Put sx70211.vhd on the mechanical hard disk, wincontig shows four fragments, and under g4e, blocklist shows three fragments. It takes 1 minute and 13 seconds to change from 0 to 100% without -l parameter. Adding -l parameter from 0 to 100% takes 1 minute and 03 seconds. G4e took 1 minute and 11 seconds.
menuentry "SX70211.vhd-svbus-l" "/VHD/SX70211.vhd" {
efiload /EFI/grub/ntfs_x64.efi
search --no-floppy --set --file $2
map --mem --rt -l $2
}
My conclusions:
1. If vhd has no fragments, adding -l parameter will greatly improve the reading speed.
2. If there are fragments in vhd, it is not too much to increase the reading speed by adding -l parameter, but it is accelerated by 10 seconds on the mechanical hard disk. After adding -l parameter, there is almost no difference between the reading speed and that of g4e (there may be card table error); The fragmented ssd has not been tested.
3. Whether there are fragments or not, whether it is direct map or map --mem with -l parameter is feasible.
Therefore, the final conclusion is that grub2' s map is best added with -l parameter.
Oh,er...This thread is talking about g4e,but I talk about grub2,it seems digress...
Edited by liuzhaoyzz, 29 December 2020 - 01:48 AM.