I use an old laptop as a DIY NAS with Debian 9.6 with a HGST HTS541010B7E610 HDD.
The HDD had Power_On_Hours of more than 37k with a Load_Cycle_Count of only 380.
After doing a short smart test with smartctl the Load_Cycle_Count started to increase rather fast and within only a few hours it increased by approx. a 100.
The loading/unloading cause audible clicking also.
The constant loading/unloading stops only if I change the APM value with hdparm to 254. Originally it was set to 128.
I am not sure yet changing the APM value how much will increase the temperature but it would be better if it didn't.
Is there anything else I could try to stop the HDD constantly loading/unloading?
If it is possible I would rather avoid to restart the computer.
Edit:
The disk is approximately 4-5 years old.
Since changing the APM value the disk runs 3°C warmer.
SMART Attributes Data Structure revision number: 16
Vendor Specific SMART Attributes with Thresholds:
ID# ATTRIBUTE_NAME FLAG VALUE WORST THRESH TYPE UPDATED WHEN_FAILED RAW_VALUE
1 Raw_Read_Error_Rate 0x002f 200 200 051 Pre-fail Always - 0
3 Spin_Up_Time 0x0027 192 190 021 Pre-fail Always - 1400
4 Start_Stop_Count 0x0032 100 100 000 Old_age Always - 80
5 Reallocated_Sector_Ct 0x0033 200 200 140 Pre-fail Always - 0
7 Seek_Error_Rate 0x002e 200 200 000 Old_age Always - 0
9 Power_On_Hours 0x0032 049 049 000 Old_age Always - 37652
10 Spin_Retry_Count 0x0032 100 253 000 Old_age Always - 0
11 Calibration_Retry_Count 0x0032 100 253 000 Old_age Always - 0
12 Power_Cycle_Count 0x0032 100 100 000 Old_age Always - 80
192 Power-Off_Retract_Count 0x0032 200 200 000 Old_age Always - 56
193 Load_Cycle_Count 0x0032 200 200 000 Old_age Always - 489
194 Temperature_Celsius 0x0022 109 099 000 Old_age Always - 34
196 Reallocated_Event_Count 0x0032 200 200 000 Old_age Always - 0
197 Current_Pending_Sector 0x0032 200 200 000 Old_age Always - 0
198 Offline_Uncorrectable 0x0030 100 253 000 Old_age Offline - 0
199 UDMA_CRC_Error_Count 0x0032 200 200 000 Old_age Always - 0
200 Multi_Zone_Error_Rate 0x0008 100 253 000 Old_age Offline - 0
Best Answer
Wikipedia S.M.A.R.T. says this about Load_Cycle_Count :
Evidently your drive decided to become "greener" and is parking the heads many times per hour. As the OS asks about the status of the disks frequently, this causes each time the heads to unpark themselves.
Your solution of setting the APM value with hdparm to 254 is the most-used one, although it raises the temperature a bit.
I can see that your disk temperature is 34 degrees. For comparison, my own HDD is currently running at 37 degrees. In general, any temperature below 50 degrees is counted as acceptable.
I would say that you have nothing to worry about and your disk is running well.