On Saturday 11 November 2017 01:49:25 Jon LaBadie wrote: > Just a thought. My amanda server has seven hard drives > dedicated to saving amanda data. Only 2 are typically > used (holding and one vtape drive) during an amdump run. > Even then, the usage is only for about 3 hours. > > So there is a lot of electricity and disk drive wear for > inactive drives. > > Can todays drives be unmounted and powered down then > when needed, powered up and mounted again? > > I'm not talking about system hibernation, the system > and its other drives still need to be active. > > Back when 300GB was a big drive I had 2 of them in > external USB housings. They shut themselves down > on inactivity. When later accessed, there would > be about 5-10 seconds delay while the drive spun > up and things proceeded normally. > > That would be a fine arrangement now if it could > be mimiced. > > Jon
Hi Jon and Gundy; This might be nice, but is it balanced with the life of the drive when it is only spun down from a power failure long enough to use up the UPS? Or when powerdown maintenance is being done. The drives in this box are all 5+ years old, and the drive I use for vtapes is the oldest. SMART Attributes Data Structure revision number: 10 Vendor Specific SMART Attributes with Thresholds: ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE 1 Raw_Read_Error_Rate 0x000f 119 099 006 Pre-fail Always - 210441924 3 Spin_Up_Time 0x0003 100 100 000 Pre-fail Always - 0 4 Start_Stop_Count 0x0032 100 100 020 Old_age Always - 378 5 Reallocated_Sector_Ct 0x0033 100 100 036 Pre-fail Always - 25 7 Seek_Error_Rate 0x000f 082 060 030 Pre-fail Always - 179617636 9 Power_On_Hours 0x0032 023 023 000 Old_age Always - 68094 10 Spin_Retry_Count 0x0013 100 100 097 Pre-fail Always - 0 12 Power_Cycle_Count 0x0032 100 100 020 Old_age Always - 383 184 End-to-End_Error 0x0032 100 100 099 Old_age Always - 0 187 Reported_Uncorrect 0x0032 100 100 000 Old_age Always - 0 188 Command_Timeout 0x0032 100 099 000 Old_age Always - 4 189 High_Fly_Writes 0x003a 001 001 000 Old_age Always - 395 190 Airflow_Temperature_Cel 0x0022 061 057 045 Old_age Always - 39 (Min/Max 18/42) 197 Current_Pending_Sector 0x0012 100 100 000 Old_age Always - 0 198 Offline_Uncorrectable 0x0010 100 100 000 Old_age Offline - 0 199 UDMA_CRC_Error_Count 0x003e 200 200 000 Old_age Always - 0 240 Head_Flying_Hours 0x0000 100 253 000 Old_age Offline - 68089 (30 52 0) 241 Total_LBAs_Written 0x0000 100 253 000 Old_age Offline - 4258864840 242 Total_LBAs_Read 0x0000 100 253 000 Old_age Offline - 3825606395 SMART Error Log Version: 1 No Errors Logged SMART Self-test log structure revision number 1 Num Test_Description Status Remaining LifeTime(hours) LBA_of_first_error # 1 Extended offline Completed without error 00% 59921 - # 2 Extended offline Completed without error 00% 54103 - # 3 Short offline Completed without error 00% 45529 - # 4 Extended offline Completed without error 00% 43537 - # 5 Extended offline Completed without error 00% 27211 - # 6 Extended offline Completed without error 00% 27043 - # 7 Extended offline Completed without error 00% 26875 - # 8 Extended offline Completed without error 00% 26372 - # 9 Extended offline Completed without error 00% 26205 - #10 Extended offline Completed without error 00% 26037 - #11 Extended offline Completed without error 00% 25869 - #12 Extended offline Completed without error 00% 25701 - #13 Extended offline Completed without error 00% 25534 - #14 Extended offline Completed without error 00% 25368 - #15 Extended offline Completed without error 00% 25201 - #16 Extended offline Completed without error 00% 25033 - #17 Extended offline Completed without error 00% 24866 - #18 Extended offline Completed without error 00% 24697 - #19 Extended offline Completed without error 00% 24530 - #20 Extended offline Completed without error 00% 24362 - #21 Extended offline Completed without error 00% 24194 - Those 25 re-allocated sectors were there the first time I used smartctl to inspect it at about 5000 spinning hours. Now at 68089 hours. Thats 7.76739676020990189 years of service. I am about to replace it with a 2Tb, not because its failing, but because its essentially full and occasionally rejects a big dump. That however has seemed to reduce amanda's reticence to do a level 2, before, despite some very loose settings, it refused to do a level 2, and still insists on promoting most level 2 to level 0's. And the level 0 then is 5 or 6 days early in a 7 day cycle. And that makes the imbalance between dump sizes worse, not better. What I also consider as very very important when buying "commodity" drives, is going to the drive makers site, getting that drives latest firmware and installing it. When Newegg et all buys those drives very early in the production cycle, they are often written with buggy firmware that can slow the data rates considerably. In one case, a drive that was doing 35 megabytes/second reads, and even slower writes, is now doing 135 both ways after having its firmware updated. Its not uncommon to gain 20 or 30 megs a second read/write rates for any drive updated. So I leave mine spinning. The head drag when landing and getting started is I am convinced is the first major cause of drive failures. Remember that a drives heads do not touch the disk but fly a few microns above on the film of air carried by the spinning disk. The other major contributor to drive failures is the bright red sata cables, use any other color but that bright red, its vapors over time convert the copper into dark brown dust that doesn't make a very good conductor of electricity. Watch your logs, and when you see a drive reset, and a flurry of them if you touch the cable, its history. And its data errors can trash a perfectly good drive as it tries to cope with them. Stop them if you must, but I think you will pay for it in seriously shortened drive life. How long, at 5 watts a drive saved, does it take to gain back the $100 it cost? I haven't bothered to work that out. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene>
