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mouseman

Member

From: Outta nowhere

Registered: 2014-04-04

Posts: 298

[Solved] SSD memory cell clearing

How do you know when memory cell clearing on an SSD is required? Is it as simple as testing whether write speeds are slow?

I own a Samsung 830 256GB, bought in june 2012 so its nearly 3 years old. It's been in use on a daily basis since. SMART data output:

ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE
  5 Reallocated_Sector_Ct   0x0033   100   100   010    Pre-fail  Always       -       0
  9 Power_On_Hours          0x0032   097   097   000    Old_age   Always       -       10462
 12 Power_Cycle_Count       0x0032   098   098   000    Old_age   Always       -       1721
177 Wear_Leveling_Count     0x0013   082   082   000    Pre-fail  Always       -       624
179 Used_Rsvd_Blk_Cnt_Tot   0x0013   100   100   010    Pre-fail  Always       -       0
181 Program_Fail_Cnt_Total  0x0032   100   100   010    Old_age   Always       -       0
182 Erase_Fail_Count_Total  0x0032   100   100   010    Old_age   Always       -       0
183 Runtime_Bad_Block       0x0013   100   100   010    Pre-fail  Always       -       0
187 Uncorrectable_Error_Cnt 0x0032   100   100   000    Old_age   Always       -       0
190 Airflow_Temperature_Cel 0x0032   066   053   000    Old_age   Always       -       34
195 ECC_Error_Rate          0x001a   200   200   000    Old_age   Always       -       0
199 CRC_Error_Count         0x003e   253   253   000    Old_age   Always       -       0
235 POR_Recovery_Count      0x0012   099   099   000    Old_age   Always       -       291
241 Total_LBAs_Written      0x0032   099   099   000    Old_age   Always       -       21808084392

SMART Error Log Version: 1
No Errors Logged

It's connected to SATA6, its got the latest firmware and partitions are aligned.

Firmware Version: CXM03B1Q
User Capacity:    256,060,514,304 bytes [256 GB]
Sector Size:      512 bytes logical/physical
SATA Version is:  SATA 3.0, 6.0 Gb/s (current: 6.0 Gb/s)

When I time a 4GB write to the SSD (from memory) I get 350MB/s. Read (after flushing caches) is slightly faster, around 450MB/s.

Thanks.

Last edited by mouseman (2015-05-12 13:23:45)

R00KIE

Forum Fellow

From: Between a computer and a chair

Registered: 2008-09-14

Posts: 4,734

Re: [Solved] SSD memory cell clearing

Check the specified read/write speeds for your ssd, if what you get is close to the specifications then don't worry about it.

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R00KIE
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mouseman

Member

From: Outta nowhere

Registered: 2014-04-04

Posts: 298

Re: [Solved] SSD memory cell clearing

Well, specs and benchmarks on the web are a bit higher, with writes topping around 410MB/s and reads topping around 520MB/s.

mouseman

Member

From: Outta nowhere

Registered: 2014-04-04

Posts: 298

Re: [Solved] SSD memory cell clearing

I went ahead and did the clear, had lunch and I'm done reinstalling and reconfiguring most stuff.

System is definitely snappier and both reading and writing are faster.

rlees85

Member

From: Daventry, UK

Registered: 2015-04-29

Posts: 98

Website

Re: [Solved] SSD memory cell clearing

wouldnt the 'discard' mount option take care of this & prevent the need to wipe from time to time ?

mouseman

Member

From: Outta nowhere

Registered: 2014-04-04

Posts: 298

Re: [Solved] SSD memory cell clearing

wouldnt the 'discard' mount option take care of this & prevent the need to wipe from time to time ?

TRIM only safeguards against file deletes, not replacements such as an incremental save.

R00KIE

Forum Fellow

From: Between a computer and a chair

Registered: 2008-09-14

Posts: 4,734

Re: [Solved] SSD memory cell clearing

wouldnt the 'discard' mount option take care of this & prevent the need to wipe from time to time ?

TRIM only safeguards against file deletes, not replacements such as an incremental save.

I suppose you could manually trim the whole filesystem. It should trim all the free space.

---

R00KIE
Tm90aGluZyB0byBzZWUgaGVyZSwgbW92ZSBhbG9uZy4K

rlees85

Member

From: Daventry, UK

Registered: 2015-04-29

Posts: 98

Website

Re: [Solved] SSD memory cell clearing

wouldnt the 'discard' mount option take care of this & prevent the need to wipe from time to time ?

TRIM only safeguards against file deletes, not replacements such as an incremental save.

Learn something new every day I've only really been running on an SSD for two weeks so still learning

mouseman

Member

From: Outta nowhere

Registered: 2014-04-04

Posts: 298

Re: [Solved] SSD memory cell clearing

wouldnt the 'discard' mount option take care of this & prevent the need to wipe from time to time ?

TRIM only safeguards against file deletes, not replacements such as an incremental save.

Learn something new every day I've only really been running on an SSD for two weeks so still learning

Do make sure you read the wiki page on SSD's and apply the finetunings they give therein. Basically you'd want to change the IO Scheduler, discard and swappiness.