Re: Weird behavior writing to SSD on 2013 MacBook

On 2015-02-04 19:29, Lundberg, Johannes wrote:
> Hi
> 
> I'm thought I was gonna do some test runs with HEAD on a 2013 Macbook Air
> and noticed some weird behavior regarding disk I/O.
> 
> This happens both when doing portsnap extract and clone from git repository.
> 
> For example portsnap extract, the extraction process (the output of it)
> suddenly stops, for seconds or maybe even minutes, quite many times during
> the whole extraction process.
> iostat reports ~200 MB/s on ada0 the whole time during freeze.
> 
> 
> pciconf:
> 
> ahci0_at_pci0:4:0:0:    class=0x010601 card=0x91831b4b chip=0x91831b4b
> rev=0x14 hdr=0x00
>     vendor     = 'Marvell Technology Group Ltd.'
>     class      = mass storage
>     subclass   = SATA
> 
> 
> dmesg (relevant lines?):
> 
> ahci0: <Marvell 88SS9183 AHCI SATA controller> port
> 0x1028-0x102f,0x1034-0x1037,0x1020-0x1027,0x1030-0x1033,0x1000-0x101f mem
> 0xb0700000-0xb07001ff at device 0.0 on pci4
> ahci0: AHCI v1.00 with 1 6Gbps ports, Port Multiplier not supported
> ahcich0: <AHCI channel> at channel 0 on ahci0
> 
> ada0 at ahcich0 bus 0 scbus0 target 0 lun 0
> ada0: <APPLE SSD SD0128F A222821> ATA-8 SATA 3.x device
> ada0: Serial Number 1325A5401681 \^T\^T\^T\^T\^T\^T\^T
> ada0: 600.000MB/s transfers (SATA 3.x, UDMA6, PIO 512bytes)
> ada0: Command Queueing enabled
> ada0: 115712MB (236978176 512 byte sectors: 16H 63S/T 16383C)
> ada0: Previously was known as ad4
> 
> GEOM: ada0: enabling Boot Camp
> GEOM: diskid/DISK-1325A5401681%20%14%14%14%14%14%14%14: enabling Boot Camp
> 
> 
> gpart:
> 
> =>       34  236978109  ada0  GPT  (113G)
>          34          6        - free -  (3.0K)
>          40     409600     1  efi  (200M)
>      409640  174519128     2  apple-hfs  (83G)
>   174928768    1269536     3  apple-boot  (620M)
>   176198304       1376        - free -  (688K)
>   176199680   29782016     4  linux-data  (14G)
>   205981696    2097152     5  linux-swap  (1.0G)
>   208078848       1600     6  efi  (800K)
>   208080448   27261368     7  freebsd-ufs  (13G)
>   235341816    1445888     8  freebsd-swap  (706M)
>   236787704     190439        - free -  (93M)
> 
> 
> One other weird thing is that FreeBSD does not show up in the refind boot
> menu by default, only OSX and Linux. I have to press ESC once to reload for
> FreeBSD boot option to show up.. Any clues? Is my partition configuration
> wrong in some way?
> 
> Thanks!
> --
> Johannes Lundberg
> BRILLIANTSERVICE CO., LTD.
> 

For the disk io bit, try running 'gstat' instead of iostat, and see what
it says.

-- 
Allan Jude