Xavier AGC eMMC durability

I’d like to know the characteristics if the eMMC flash of the Xavier devices we will be using, in order to get a feeling of the lifetime with our current write load on the storage.
I assume (!) it’s a Hynix hbg4a2 32gb emmc flash.

I’d like to know the erase block size (I assume it’s 4 MB) and the max erase cycle count. Then i can get a feeling when we approach the wear level threshold using our write load.

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Hi, the P/N is H26M64208EMRN from Hynix. There is no ‘erase block size’ and ‘erase cycle’ in data sheet, only ‘erase group size’ = 512KB. We are checking internally, you can check with Hynix in parallel.

The only info from the Hynix website

Product Grade
AAT/AIT part is in compliance with AEC-Q100 and also developed based on the Automotive base-line.
IT part is in compliance with TS16949 and provides the same device longevity as AT parts.

Have not found any other information about this part on their website.

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Also please try CMD8 and CMD9 to get CSD and EXT_CSD table for detail info of eMMC.

That shows me “only” the erase size, and in CSD_EXT the write speed, but not the number how often a block can be rewritten before failing.
That’s important to decide if an SSD/NVMe module should be added to sustain the average write load from the application for the projected lifetime of the Xavier.

There is no such number of a block in datasheet and as far as I know. In general, the P/E cycles standard are 100,000 for SLC, 3,000 for MLC and 1000 for TLC. The lifetime of eMMC is calculated based on the real P/E cycles of chip and the standard. The estimated value is stored in register of DEVICE_LIFE_TIME_EST_TYP_A/B in CSD_EXT.

The problem is that we would like top know when the flash will start to fail for a write load of
600 KBytes/minute for 12 hours and 6 days a week and we need to swap the Xavier for a new one, or if it’s cheaper to add a SSD disk or NVMe card before installing it.

You can calculate the lifetime based on 32GB, 600KB/m for 12hr x6 and P/E standard. Please search the detail calculation formula/method online.