RAID 5 Fájl másolásnál leesik a sebesség

Olyan problémám volna, hogy Raid 5-ös kötetre másolásnál leesik a sebesség.
Amikor elindítom a másolást akkor kb a fájl negyedéig ~100 Mbps utána szinte leáll kb 10 másodprecig.
Utána megint megy pár másodpercig, és utána megint leáll.
Ezt csinálja innentől kezdve a fájl másolás végéig (raid kötetre íráskor).
Ha a raidről másolok máshova akkor ilyen jelenség nincs.

Raid kártya: LSI MegaRaid SAS 9261-8i

/opt/lsi/MegaCLI # ./MegaCli -LDInfo -Lall -aALL
Adapter 0 -- Virtual Drive Information:
Virtual Drive: 0 (Target Id: 0)
Name :
RAID Level : Primary-5, Secondary-0, RAID Level Qualifier-3
Size : 4.089 TB
Sector Size : 512
Is VD emulated : Yes
Parity Size : 1.363 TB
State : Optimal
Strip Size : 64 KB
Number Of Drives : 4
Span Depth : 1
Default Cache Policy: WriteBack, ReadAhead, Cached, No Write Cache if Bad BBU
Current Cache Policy: WriteThrough, ReadAhead, Cached, No Write Cache if Bad BBU
Default Access Policy: Read/Write
Current Access Policy: Read/Write
Disk Cache Policy : Disabled
Encryption Type : None
Is VD Cached: No

/opt/lsi/MegaCLI # ./MegaCli -PDList -aALL

Adapter #0

Enclosure Device ID: 252
Slot Number: 0
Drive's position: DiskGroup: 0, Span: 0, Arm: 0
Enclosure position: N/A
Device Id: 3
WWN: 50014ee25eaec146
Sequence Number: 6
Media Error Count: 0
Other Error Count: 0
Predictive Failure Count: 0
Last Predictive Failure Event Seq Number: 0
PD Type: SATA

Raw Size: 1.819 TB [0xe8e088b0 Sectors]
Non Coerced Size: 1.818 TB [0xe8d088b0 Sectors]
Coerced Size: 1.817 TB [0xe8b6d000 Sectors]
Sector Size: 0
Logical Sector Size: 0
Physical Sector Size: 0
Firmware state: Online, Spun Up
Commissioned Spare : No
Emergency Spare : No
Device Firmware Level: 0A80
Shield Counter: 0
Successful diagnostics completion on : N/A
SAS Address(0): 0x4433221103000000
Connected Port Number: 3(path0)
Inquiry Data: WD-WCC4M0683248WDC WD20EZRX-00D8PB0 80.00A80
FDE Capable: Not Capable
FDE Enable: Disable
Secured: Unsecured
Locked: Unlocked
Needs EKM Attention: No
Foreign State: None
Device Speed: 6.0Gb/s
Link Speed: 6.0Gb/s
Media Type: Hard Disk Device
Drive: Not Certified
Drive Temperature :36C (96.80 F)
PI Eligibility: No
Drive is formatted for PI information: No
PI: No PI
Port-0 :
Port status: Active
Port's Linkspeed: 6.0Gb/s
Drive has flagged a S.M.A.R.T alert : No

Enclosure Device ID: 252
Slot Number: 1
Drive's position: DiskGroup: 0, Span: 0, Arm: 1
Enclosure position: N/A
Device Id: 2
WWN: 50014ee656028d20
Sequence Number: 6
Media Error Count: 0
Other Error Count: 0
Predictive Failure Count: 0
Last Predictive Failure Event Seq Number: 0
PD Type: SATA

Raw Size: 1.364 TB [0xaea87b30 Sectors]
Non Coerced Size: 1.363 TB [0xae987b30 Sectors]
Coerced Size: 1.363 TB [0xae81a800 Sectors]
Sector Size: 0
Logical Sector Size: 0
Physical Sector Size: 0
Firmware state: Online, Spun Up
Commissioned Spare : No
Emergency Spare : No
Device Firmware Level: AB51
Shield Counter: 0
Successful diagnostics completion on : N/A
SAS Address(0): 0x4433221102000000
Connected Port Number: 2(path0)
Inquiry Data: WD-WMAZA2604663WDC WD15EARS-00MVWB0 51.0AB51
FDE Capable: Not Capable
FDE Enable: Disable
Secured: Unsecured
Locked: Unlocked
Needs EKM Attention: No
Foreign State: None
Device Speed: 3.0Gb/s
Link Speed: 3.0Gb/s
Media Type: Hard Disk Device
Drive: Not Certified
Drive Temperature :36C (96.80 F)
PI Eligibility: No
Drive is formatted for PI information: No
PI: No PI
Port-0 :
Port status: Active
Port's Linkspeed: 3.0Gb/s
Drive has flagged a S.M.A.R.T alert : No

Enclosure Device ID: 252
Slot Number: 2
Drive's position: DiskGroup: 0, Span: 0, Arm: 2
Enclosure position: N/A
Device Id: 1
WWN: 50014ee600cb5a39
Sequence Number: 6
Media Error Count: 0
Other Error Count: 0
Predictive Failure Count: 0
Last Predictive Failure Event Seq Number: 0
PD Type: SATA

Raw Size: 1.364 TB [0xaea87b30 Sectors]
Non Coerced Size: 1.363 TB [0xae987b30 Sectors]
Coerced Size: 1.363 TB [0xae81a800 Sectors]
Sector Size: 0
Logical Sector Size: 0
Physical Sector Size: 0
Firmware state: Online, Spun Up
Commissioned Spare : No
Emergency Spare : No
Device Firmware Level: AB51
Shield Counter: 0
Successful diagnostics completion on : N/A
SAS Address(0): 0x4433221101000000
Connected Port Number: 1(path0)
Inquiry Data: WD-WMAZA3245384WDC WD15EARS-00MVWB0 51.0AB51
FDE Capable: Not Capable
FDE Enable: Disable
Secured: Unsecured
Locked: Unlocked
Needs EKM Attention: No
Foreign State: None
Device Speed: 3.0Gb/s
Link Speed: 3.0Gb/s
Media Type: Hard Disk Device
Drive: Not Certified
Drive Temperature :36C (96.80 F)
PI Eligibility: No
Drive is formatted for PI information: No
PI: No PI
Port-0 :
Port status: Active
Port's Linkspeed: 3.0Gb/s
Drive has flagged a S.M.A.R.T alert : No

Enclosure Device ID: 252
Slot Number: 3
Drive's position: DiskGroup: 0, Span: 0, Arm: 3
Enclosure position: N/A
Device Id: 0
WWN: 50014ee6ab57df40
Sequence Number: 6
Media Error Count: 0
Other Error Count: 0
Predictive Failure Count: 0
Last Predictive Failure Event Seq Number: 0
PD Type: SATA

Raw Size: 1.364 TB [0xaea87b30 Sectors]
Non Coerced Size: 1.363 TB [0xae987b30 Sectors]
Coerced Size: 1.363 TB [0xae81a800 Sectors]
Sector Size: 0
Logical Sector Size: 0
Physical Sector Size: 0
Firmware state: Online, Spun Up
Commissioned Spare : No
Emergency Spare : No
Device Firmware Level: AB51
Shield Counter: 0
Successful diagnostics completion on : N/A
SAS Address(0): 0x4433221100000000
Connected Port Number: 0(path0)
Inquiry Data: WD-WMAZA2607767WDC WD15EARS-00MVWB0 51.0AB51
FDE Capable: Not Capable
FDE Enable: Disable
Secured: Unsecured
Locked: Unlocked
Needs EKM Attention: No
Foreign State: None
Device Speed: 3.0Gb/s
Link Speed: 3.0Gb/s
Media Type: Hard Disk Device
Drive: Not Certified
Drive Temperature :36C (96.80 F)
PI Eligibility: No
Drive is formatted for PI information: No
PI: No PI
Port-0 :
Port status: Active
Port's Linkspeed: 3.0Gb/s
Drive has flagged a S.M.A.R.T alert : No

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