[not a bug, help] - Data written into the file and data on the physical HD do not match #2
Description
Hi Cyberax,
I'm having an issue with the script, I doubt it requires any changes to it, but this is really the only way I could find to contact you.
I just purchased two of the crucial M4 ssds, and set each partition up in a in a raid 1 with MDADM. As far as I can tell, I did everything right, everything is working, except trim. When I use the hdparm fibmap & read-sector test, I do not see zeros, as I did with my old vertex2.
Looking around online, it appears that this is caused by no support for discard in the raid1 module. There's the thread on LWN about a patch, which you have probably read, but it's not committed yet, and it's probably going to be some time before it is.
I bet if I failed the raid and just operated on each drive one at a time, discard would work. I was going to go about figuring out how to do that, but then I found your script, which looks like a perfectly fine work around until the kernel supports it. I did this with wiper.sh for a few years.. I tried the script, but I get stuck at:
print "Checking misalignment signatures"
for sl in slaves.values():
slave_offset = sl["offset"]*sector_size
for rng in trim_ranges:
for test in rng["test_data"].values():
# snip...
sector_data = data + ' '*padding + data
what_we_read = string_at(read_buf+read_buf_offset, sector_size)
if what_we_read != sector_data:
print "Data written into the file and data on the physical HD do not match!"
sys.exit(2)
what_we_read is: empty string
sector_data is something like:
Zb45aa627634f4682950f49b4e9e9f8a0
b45aa627634f4682950f49b4e9e9f8a0A
Any ideas why that would happen and what I can try next to fix it? Is it a hole in the script, or is something horribly wrong with my setup, or even a hardware problem?
Thanks