I recently bought two 8TB Toshiba NAS drives and upon installing them started to preclear them both. They both ran pretty much in parallel for pre-read and write taking around 10 hours for each phase. But when the post-read started one finished in around 10 hours again, but the other drive started to read slower and slower. Speeds have dropped to 2MB/s. It is at 76% and has been running for 23 hours. SMART doesn't seem to report any issues but I can't get the process to complete any quicker. Is this an issue with the drive? Any help would be greatly appreciated.
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# Unraid Server Preclear of disk 8120A00CFA3H #
# Cycle 1 of 1, partition start on sector 64. #
# #
# Step 1 of 5 - Pre-read verification: [10:52:04 @ 204 MB/s] SUCCESS #
# Step 2 of 5 - Zeroing the disk: [10:53:29 @ 204 MB/s] SUCCESS #
# Step 3 of 5 - Writing Unraid's Preclear signature: SUCCESS #
# Step 4 of 5 - Verifying Unraid's Preclear signature: SUCCESS #
# Step 5 of 5 - Post-Read in progress: (76% Done) #
# #
# ** Time elapsed: 23:13:43 | Current speed: 3 MB/s | Average speed: 72 MB/s #
# #
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# Cycle elapsed time: 44:59:36 | Total elapsed time: 44:59:36 #
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# S.M.A.R.T. Status (device type: default) #
# #
# ATTRIBUTE INITIAL STATUS #
# Reallocated_Sector_Ct 0 - #
# Power_On_Hours 0 - #
# Temperature_Celsius 26 - #
# Reallocated_Event_Count 0 - #
# Current_Pending_Sector 0 - #
# Offline_Uncorrectable 0 - #
# UDMA_CRC_Error_Count 0 - #
# #
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# SMART overall-health self-assessment test result: PASSED #
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