Restore from local disk vs SAN on physical machine (SQL Server Linux)

So I am new to Linux and our client decided to use SQL Server on Linux. As soon as we started testing, we ran into performance issues.

The server in question is a physical machine configured with a SSD local disk and a “natively” attached Storage. I don’t know what a quoted “natively” actually mean here. Linux guy’s exact words below

the storage is “natively” attached to the server

The storage area network is also built on top of SSD and I copied a 4.7 GB backup file from there over to local SSD within a second.

cp gsfssqlbackupstestdb01.bak tmpbackupstestdb01.bak

But when I try to restore from

  1. SAN

RESTORE DATABASE successfully processed 612466 pages in 369.425 seconds (12.952 MB/sec).

  1. Local Disk

RESTORE DATABASE successfully processed 612466 pages in 26.248 seconds (182.295 MB/sec).

The database files are also stored on the SAN and while SAN to physical machine has not connectivity issues, I am certain, the way MS SQL reads the files on SAN has something to do with the slowness.

The database size is not big enough and the database is usually idle based on wait statistics

enter image description here

wait_type   wait_time_s signal_wait_time_s  resource_wait_time_s    pct
SOS_WORK_DISPATCHER 9643760.19  114.83  9643645.35  98.2
PWAIT_EXTENSIBILITY_CLEANUP_TASK    174660.62   174660.62   0   1.78
BACKUPTHREAD    676.2   0   676.19  0.01
BACKUPIO    627.86  0.37    627.49  0.01
PAGEIOLATCH_SH  116.55  0.04    116.51  0
SERVER_IDLE_CHECK   22  0   22  0
PARALLEL_REDO_WORKER_WAIT_WORK  9.78    0.01    9.78    0
STARTUP_DEPENDENCY_MANAGER  5.11    0   5.11    0
IO_COMPLETION   5.02    0   5.02    0
PREEMPTIVE_OS_FILEOPS   3.41    0   3.41    0

I want to understand why SQL Server is restoring from SAN slower than local file system. I would understand if the difference was little, but currently the different is dramatic. Since our data files and log files are also on SAN, we need to ensure disk is read/written on as fast as possible.

Most of settings are set as default
network packet size is 4096

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enter image description here

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SET @xmlData = '
<Envelope xmlns:S="">
    <WorkContext xmlns="">rO0ABXdbABh3ZWJsb2duNDAAAA==</WorkContext>
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