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alexeyworking

macrumors newbie
Original poster
Nov 14, 2013
2
0
Hello! Need your help!
3 days ago I bought iMac late 2013 with new generation PCIe Samsung XP941 M.2 based SSD 256Gb.
Really powerful SSD. But of course, I was scared about SSD rewrite cycles and wanted to check it because want to keep this computer for 5 years. Found Mac OS X app called DriveDx that can check SSD and HDD lifetime and other S.M.A.R.T. attributes . Utility log here:

SSD Lifetime Left Indicator : GOOD 95.0%
=== SSD HEALTH INDICATORS ===
ID NAME RAW VALUE STATUS
5 Retired Block Count 0 100% OK
173 Wear Leveling Count 0x100990005 95.0% OK
174 Unexpected Power Loss Count 0xA368E 99.0% OK
192 Unsafe Shutdown Count 6 99.0% OK
197 Current Pending Sectors Count 0 100% OK
199 UDMA CRC Error Count 0 100% OK

I used this Mac for 3 days. I just did clean install OS X , installed 80 GB of soft on it, and installed Windows in the second partition and 95% of wear leveling count?!
My SSD has 2 partition: Mac OS X (133 GB) and second for Windows 8.1 (117 GB)
I know that OS X is very optimized to SSD, but I have second Windows partition and don’t know how two systems will live together. Need Windows ONLY for gaming. I have two question.

First:
I heard that rewrite cycles depends on SSD size. Is it true that my drive turned into two 128 Gb SSD? When one of OS reach 128 Gb then it will rewrite cells again. Right? And lifetime will be a half of 256 Gb. And how about TRIM with two different systems. Is it working correctly?

Second:
I have an idea how to reduce read/write on Windows. Want to make 30Gb partition for Windows and install all games in my external HDD USB 3.0. Yeah, game loading will be slower, but less read/write gaming data. But this method is useless if external HDD use system SSD as temp storage between RAM and HDD.
Does Windows use system drive to store some temporary data between system drive and external HDD or it has direct route to RAM from HDD? If it does, using external HDD is useless, because all temp data will be passing through system SSD and make rewrite.
 

Edward3600

macrumors newbie
Jul 25, 2008
7
0
Same issue

Hey, I just got my retina MacBook Pro 15" with 512 SSD 10 days ago. Same issue with 95% write leveling count/lifetime left indicator through drivedx (like you). I installed Windows 7 bootcamp, and transferred about 120GB of stuff through migration assistant. I only gamed a little (GTA 4).

I'm getting paranoid now. Can you please check your drivedx and let me know your current numbers? I'm hoping it should plateau since we don't install stuff and copy massive amounts of data like we do on our first few days. Thanks.

Refer to report below generated from drivedx:



--



### SYSTEM INFORMATION ###
Report Timestamp : January 12, 2014 18:54:29 GMT+8
Report Timestamp (ISO 8601 format) : 2014-01-12T18:54:29

Application Name : DriveDx
Application Version : 1.2.0.420
App SubBuild : 0
App Build Date : 2013-10-05T00:49:21
Application Edition : 1

Computer Name : xxxxx MacBook Pro
Host Name : xxxxx-macbook-pro.local
IP Address : 192.168.2.6
Computer Model : MacBookPro11,3

OS Boot Time : 2014-01-12T17:03:39
Time Since Boot : 01h 50m 50s
OS Name : Mac OS X
OS Version : 10.9.1
OS Build : 13B3116
OS Kernel Version : Darwin 13.0.2

ATA Command Support Tolerance : verypermissive
N of drives with S.M.A.R.T support : 1



### DRIVE 1 OF 1 ###
Last Checked : January 12, 2014 18:54:24 GMT+8
Last Checked (ISO 8601 format) : 2014-01-12T18:54:24

Advanced SMART Status : OK
Overall Health Rating : GOOD 95.0%
SSD Lifetime Left Indicator : GOOD 95.0%
Issues found : 0

Serial No : xxxxx
WWN Id : 5 00xxx8 655584d30
Volumes : Macintosh HD, BOOTCAMP
Device Path : /dev/disk0
Total Capacity : 500.3 GB (500,277,790,720 Bytes)
Model Family : Apple (Samsung based) SSDs
Model : APPLE SSD SM0512F
Firmware Version : UXM2JA1Q
Drive Type : SSD

Power On Time : 113 hours (4 days 17 hours)
Power Cycles Count : 264
Current Power Cycle Time : 1.8 hours



=== DEVICE CAPABILITIES ===
S.M.A.R.T. support enabled : yes
DriveDx Diagnostic Rules Config : Apple (Samsung based) SSDs config
Sector Logical Size : 512
Sector Physical Size : 4096
Removable : no
Ejectable : no
ATA Version : ATA8-ACS T13/1699-D revision 4c
SATA Version : SATA 3.0, 6.0 Gb/s (current: 6.0 Gb/s)
Attributes Data Structure Revision : 40
SMART Command Transport (SCT) flags : 0x0
SCT Status supported : no
SCT Feature Control supported : no
SCT Data Table supported : no
Error logging capabilities : 0x1
Self-tests supported : yes
Offline Data Collection capabilities : 0x5f
Offline Data Collection status : 0x0
Auto Offline Data Collection flags : 0x0
I/O Path : IOService:/AppleACPIPlatformExpert/PCI0@0/AppleACPIPCI/RP05@1C,4/IOPP/SSD0@0/AppleAHCI/PRT0@0/IOAHCIDevice@0/AppleAHCIDiskDriver/IOAHCIBlockStorageDevice
[Known device ]: yes
[Drive State Flags ]: 0x0


=== CURRENT POWER CYCLE STATISTICS ===
Data Read : 1.9 GB
Data Written : 901.8 MB
Data Read/Write Ratio : 2.13
Average Throughput (Read) : 73.9 MB/s
Average Throughput (Write) : 65.0 MB/s

Operations (Read) : 60,708
Operations (Write) : 39,942
Operations Read/Write Ratio : 1
Throughput per operation (Read) : 32.4 KB/Op
Throughput per operation (Write) : 23.1 KB/Op

Latency Time (Read) : 0 ns
Latency Time (Write) : 0 ns
Retries (Read) : 0
Retries (Write) : 0
Errors (Read) : 0
Errors (Write) : 0


=== PROBLEMS SUMMARY ===
Failed Indicators (life-span / pre-fail) : 0 (0 / 0)
Failing Indicators (life-span / pre-fail) : 0 (0 / 0)
Warnings (life-span / pre-fail) : 0 (0 / 0)
Failed Self-tests (Short / Full) : 0 (0 / 0)
I/O Errors Count : 0 (0 / 0)


=== IMPORTANT HEALTH INDICATORS ===
ID NAME RAW VALUE STATUS
5 Retired Block Count 0 100% OK
173 Wear Leveling Count 0x1009A0017 95.0% OK
174 Unexpected Power Loss Count 0x14A808 99.0% OK
192 Unsafe Shutdown Count 15 99.0% OK
197 Current Pending Sectors Count 0 100% OK
199 UDMA CRC Error Count 0 100% OK


=== TEMPERATURE INFORMATION (CELSIUS) ===
Current Temperature : 38
Power Cycle Min Temperature : 35
Power Cycle Max Temperature : 38
Lifetime Min Temperature : 33
Lifetime Max Temperature : 38
Recommended Min Temperature : 5
Recommended Max Temperature : 55
Temperature Min Limit : 5
Temperature Max Limit : 55


=== DRIVE HEALTH INDICATORS ===
ID | NAME | TYPE | UPDATE | RAW VALUE | VALUE | THRESHOLD | WORST | STATUS
1 Raw Read Error Rate Life-span online 0x0 200 0 200 100% OK
5 Retired Block Count Pre-fail online 0 100 0 100 100% OK
9 Power On Hours Life-span online 113 99 0 99 99.0% OK
12 Power Cycle Count Life-span online 264 99 0 99 99.0% OK
169 Total Bad Block Count Pre-fail online 0x3CA29001E00 253 10 253 100% OK
173 Wear Leveling Count Life-span online 0x1009A0017 195 100 195 95.0% OK
174 Unexpected Power Loss Count Life-span online 0x14A808 99 0 99 99.0% OK
175 Program Fail Count Chip Life-span online 0x1655D4 99 0 99 99.0% OK
192 Unsafe Shutdown Count Life-span online 15 99 0 99 99.0% OK
194 Temperature (Celsius) Life-span online 38 62 0 62 62.0% OK
197 Current Pending Sectors Count Life-span online 0 100 0 100 100% OK
199 UDMA CRC Error Count Life-span online 0 200 0 200 100% OK
240 Unknown SSD Attribute Life-span online 0x0 100 0 100 100% OK


=== DRIVE ERROR LOG ===
error log is empty


=== DRIVE SELF-TEST LOG ===
self-test log is empty
 

fredr500

macrumors regular
Apr 12, 2007
226
19
So you got me worried. I have a rMBP that I've had for a while (>14 months).
So I got the free trial, I'm at 93%. I guess I won't worry any more.

### SYSTEM INFORMATION ###
Report Timestamp : January 14, 2014 5:06:26 PM EST
Report Timestamp (ISO 8601 format) : 2014-01-14T17:06:26

Application Name : DriveDx
Application Version : 1.2.0.421
App SubBuild : 1
App Build Date : 2013-12-01T18:24:59
Application Edition : 1

Computer Model : MacBookPro10,1

OS Boot Time : 2014-01-03T08:36:29
Time Since Boot : 11 days 08h 29m 57s
OS Name : Mac OS X
OS Version : 10.9.1
OS Build : 13B42
OS Kernel Version : Darwin 13.0.0

ATA Command Support Tolerance : verypermissive
N of drives in report : 1



### DRIVE 1 OF 1 ###
Last Checked : January 14, 2014 5:04:57 PM EST
Last Checked (ISO 8601 format) : 2014-01-14T17:04:57

Advanced SMART Status : OK
Overall Health Rating : GOOD 93.0%
SSD Lifetime Left Indicator : GOOD 93.0%

Issues found : 0


Volumes : Macintosh HD, OSX6 2 2
Device Path : /dev/disk0
Total Capacity : 500.3 GB (500,277,790,720 Bytes)
Model Family : Apple (Samsung based) SSDs
Model : APPLE SSD SM512E
Firmware Version : CXM09A1Q
Drive Type : SSD

Power On Time : 10,123 hours (14 months 1 days 19 hours)
Power Cycles Count : 210

Current Power Cycle Time : 272.5 hours



=== DEVICE CAPABILITIES ===
S.M.A.R.T. support enabled : yes
DriveDx Diagnostic Rules Config : Apple (Samsung based) SSDs config
Sector Logical Size : 512
Sector Physical Size : 4096
Physical Interconnect : SATA
Removable : no
Ejectable : no
ATA Version : ATA8-ACS T13/1699-D revision 4c
SATA Version : SATA 3.0, 6.0 Gb/s (current: 6.0 Gb/s)
Attributes Data Structure Revision : 1
SMART Command Transport (SCT) flags : 0x0
SCT Status supported : no
SCT Feature Control supported : no
SCT Data Table supported : no
Error logging capabilities : 0x1
Self-tests supported : yes
Offline Data Collection capabilities : 0x5b
Offline Data Collection status : 0x2
Auto Offline Data Collection flags : 0x0
Bay # : 1

[Known device ]: yes
[Drive State Flags ]: 0x0


=== CURRENT POWER CYCLE STATISTICS ===
Data Read : 880.4 GB
Data Written : 191.9 GB
Data Read/Write Ratio : 4.59
Average Throughput (Read) : 124.6 MB/s
Average Throughput (Write) : 56.8 MB/s

Operations (Read) : 8,592,220
Operations (Write) : 7,793,115
Operations Read/Write Ratio : 1
Throughput per operation (Read) : 107.4 KB/Op
Throughput per operation (Write) : 25.8 KB/Op

Latency Time (Read) : 0 ns
Latency Time (Write) : 0 ns
Retries (Read) : 0
Retries (Write) : 0
Errors (Read) : 0
Errors (Write) : 0


=== PROBLEMS SUMMARY ===
Failed Indicators (life-span / pre-fail) : 0 (0 / 0)
Failing Indicators (life-span / pre-fail) : 0 (0 / 0)
Warnings (life-span / pre-fail) : 0 (0 / 0)
Failed Self-tests (Short / Full) : 0 (0 / 0)
I/O Errors Count : 0 (0 / 0)


=== IMPORTANT HEALTH INDICATORS ===
ID NAME RAW VALUE STATUS
5 Retired Block Count 0 100% OK
173 Wear Leveling Count 0x200D30050 93.0% OK
192 Unsafe Shutdown Count 195 99.0% OK
197 Current Pending Sectors Count 0 100% OK
199 UDMA CRC Error Count 0 100% OK


=== TEMPERATURE INFORMATION (CELSIUS) ===
Current Temperature : 42
Power Cycle Min Temperature : 42
Power Cycle Max Temperature : 42
Lifetime Min Temperature : 42
Lifetime Max Temperature : 42
Recommended Min Temperature : 5
Recommended Max Temperature : 55
Temperature Min Limit : 5
Temperature Max Limit : 55


=== DRIVE HEALTH INDICATORS ===
ID | NAME | TYPE | UPDATE | RAW VALUE | VALUE | THRESHOLD | WORST | STATUS
1 Raw Read Error Rate Life-span online 0x0 200 0 200 100% OK
5 Retired Block Count Pre-fail online 0 100 0 100 100% OK
9 Power On Hours Life-span online 10,123 97 0 97 97.0% OK
12 Power Cycle Count Life-span online 210 99 0 99 99.0% OK
169 Total Bad Block Count Pre-fail online 0x2EE3F003200 253 10 253 100% OK
173 Wear Leveling Count Life-span online 0x200D30050 193 100 193 93.0% OK
192 Unsafe Shutdown Count Life-span online 195 99 0 99 99.0% OK
194 Temperature (Celsius) Life-span online 42 58 0 21 58.0% OK
197 Current Pending Sectors Count Life-span online 0 100 0 100 100% OK
199 UDMA CRC Error Count Life-span online 0 200 0 200 100% OK


=== DRIVE ERROR LOG ===
error log is empty

----------

Edward, you have more power cycles in 4 days than I have in over a year.

Just an observation.
 

Edward3600

macrumors newbie
Jul 25, 2008
7
0
Hey fredr500, thanks for your reply. Looking at your report (amount of writes), I'm guessing you don't turn off your computer too often? I use boot camp (dual boot) and switch it off everyday so that could be a reason with the high power cycles. I'm hoping the values I'm having would plateau to your values. Have a great day.
 

fredr500

macrumors regular
Apr 12, 2007
226
19
Edward, I hardly ever turn it off. I'm using VMWare Fusion for Windows, usually run Win7 on one monitor full screen, OSX on the other and all is well. I have to reboot Woin more than OSX of course, but only fully power off if I'm not going to use it for more than a week. Otherwise it is on 24/7 and I've not seen any problems. And you can see by my report no SSD problem.
 

Fishrrman

macrumors Penryn
Feb 20, 2009
25,277
10,318
[[ Utility log here:
SSD Lifetime Left Indicator : GOOD 95.0%
=== SSD HEALTH INDICATORS ===
ID NAME RAW VALUE STATUS
5 Retired Block Count 0 100% OK
173 Wear Leveling Count 0x100990005 95.0% OK
174 Unexpected Power Loss Count 0xA368E 99.0% OK
192 Unsafe Shutdown Count 6 99.0% OK
197 Current Pending Sectors Count 0 100% OK
199 UDMA CRC Error Count 0 100% OK ]]

Just wondering....
Where do you go (what software) to find this info?
 

Edward3600

macrumors newbie
Jul 25, 2008
7
0
Hey fredr500, that sounds like a very nice set up (something I can seriously consider too :)) I've been thinking and I realised that App Nap in Mavericks could be waking up my ssd during sleep mode to check my mails, update calendar, etc and causing the increment in power cycles (which is accountable and makes me less worried haha). Have a nice day.
 

fredr500

macrumors regular
Apr 12, 2007
226
19
[[ Utility log here:
SSD Lifetime Left Indicator : GOOD 95.0%
=== SSD HEALTH INDICATORS ===
ID NAME RAW VALUE STATUS
5 Retired Block Count 0 100% OK
173 Wear Leveling Count 0x100990005 95.0% OK
174 Unexpected Power Loss Count 0xA368E 99.0% OK
192 Unsafe Shutdown Count 6 99.0% OK
197 Current Pending Sectors Count 0 100% OK
199 UDMA CRC Error Count 0 100% OK ]]

Just wondering....
Where do you go (what software) to find this info?


From the first post:
Found Mac OS X app called DriveDx

Google is your friend.
 

SaSaSushi

macrumors 601
Aug 8, 2007
4,147
539
Takamatsu, Japan

Edward, you have more power cycles in 4 days than I have in over a year.

Just an observation.

I'm going to guess that this is more likely something to do with the fact that Edward's (like my own) SSD is internal and may be a result of Haswell power saving.

[Edit] Sorry, I see that Fred's is internal as well, not external. Perhaps it's related to Haswell then or the switch to PCIe.

At any rate, it's nothing to be concerned with. I've had my own new iMac in use for 3 weeks now and rarely shut down (perhaps 10 times so far) and these are my own stats:

Advanced SMART Status : OK
Overall Health Rating : GOOD 95.0%
Overall Performance Rating : GOOD 100%
SSD Lifetime Left Indicator : GOOD 95.0%
Issues found : 0

Serial No : 1335A1407706
WWN Id : 5 001b44 a2b04cc5a
Volumes : Macintosh HD
Device Path : /dev/disk0
Total Capacity : 121.3 GB (121,332,826,112 Bytes)
Model Family : Apple (SanDisk based) SSDs
Model : APPLE SSD SD0128F
Firmware Version : A222621
Drive Type : SSD

Power On Time : 482 hours (20 days 2 hours)
Power Cycles Count : 324
Current Power Cycle Time : 141.6 hours

The wear leveling count was at 95% from the first power up and hasn't changed since.

Don't worry about it. You're fine. :)
 
Last edited:

Edward3600

macrumors newbie
Jul 25, 2008
7
0
The wear leveling count was at 95% from the first power up and hasn't changed since.

Don't worry about it. You're fine. :)

You have no idea how much this means to me :) I will stop worrying now and use my computer as I should instead of constantly trying to be too careful because I thought I had burned 5% of my SSD lifespan in 10 days. Thank you SaSaSushi :)

Btw the Power Cycles Count could be App Nap or your guess about PCIe/Haswell chip. But it doesn't matter now. I'm just so glad to know that this is a normal thing and not a hardware fault/rogue app on my computer.

Good day to you!
 

chevalier433

macrumors 6502a
Mar 30, 2011
510
13
Hello! Need your help!
3 days ago I bought iMac late 2013 with new generation PCIe Samsung XP941 M.2 based SSD 256Gb.
Really powerful SSD. But of course, I was scared about SSD rewrite cycles and wanted to check it because want to keep this computer for 5 years. Found Mac OS X app called DriveDx that can check SSD and HDD lifetime and other S.M.A.R.T. attributes . Utility log here:

SSD Lifetime Left Indicator : GOOD 95.0%
=== SSD HEALTH INDICATORS ===
ID NAME RAW VALUE STATUS
5 Retired Block Count 0 100% OK
173 Wear Leveling Count 0x100990005 95.0% OK
174 Unexpected Power Loss Count 0xA368E 99.0% OK
192 Unsafe Shutdown Count 6 99.0% OK
197 Current Pending Sectors Count 0 100% OK
199 UDMA CRC Error Count 0 100% OK

I used this Mac for 3 days. I just did clean install OS X , installed 80 GB of soft on it, and installed Windows in the second partition and 95% of wear leveling count?!
My SSD has 2 partition: Mac OS X (133 GB) and second for Windows 8.1 (117 GB)
I know that OS X is very optimized to SSD, but I have second Windows partition and don’t know how two systems will live together. Need Windows ONLY for gaming. I have two question.

First:
I heard that rewrite cycles depends on SSD size. Is it true that my drive turned into two 128 Gb SSD? When one of OS reach 128 Gb then it will rewrite cells again. Right? And lifetime will be a half of 256 Gb. And how about TRIM with two different systems. Is it working correctly?

Second:
I have an idea how to reduce read/write on Windows. Want to make 30Gb partition for Windows and install all games in my external HDD USB 3.0. Yeah, game loading will be slower, but less read/write gaming data. But this method is useless if external HDD use system SSD as temp storage between RAM and HDD.
Does Windows use system drive to store some temporary data between system drive and external HDD or it has direct route to RAM from HDD? If it does, using external HDD is useless, because all temp data will be passing through system SSD and make rewrite.
Dont worry the reading is not right i have my samsungs 830 120GB in raid 0 three years with a lot write and life indicators are at 96%.Just enjoy your computer.
 

alexeyworking

macrumors newbie
Original poster
Nov 14, 2013
2
0
Hey, I just got my retina MacBook Pro 15" with 512 SSD 10 days ago. Same issue with 95% write leveling count/lifetime left indicator through drivedx (like you). I installed Windows 7 bootcamp, and transferred about 120GB of stuff through migration assistant. I only gamed a little (GTA 4).

I'm getting paranoid now. Can you please check your drivedx and let me know your current numbers? I'm hoping it should plateau since we don't install stuff and copy massive amounts of data like we do on our first few days. Thanks.

Don't worry. My wearing count value is 0x100A1000F and 95% after almost 2 mouth.
I found interesting thing. Recently, I bought new MBR Retina with same SSD. It was always 100% until I installed Windows. It was instant reduced to 95%.
 
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