I have a PC with a LSI Megaraid 9260-16i, and 12 WD Red 4TB disks in RAID 5. Cache is enabled, and a battery unit is installed.
The read performance (copying large files) is OK, but writing large files is painfully slow (40-50MB/s, and this is a single copy at a time, which is kind of what I would expect from a software RAID). I had another PC with a similar set up, but with an Adaptec card and Hitachi drives (12 as well) and the write speed was more like 300MB/s.
In your experience, is there anything I may have misconfigured, or is this the sort of experience I should expect with 12 disks in RAID 5 on an LSI card, or is it possible that some of the disks may have a technical problem (and if that is the case, is there any way to troubleshoot that?).
I put the config below (and the info for the first physical disk, all others have the same config) if it helps.
Thanks in advance!
============================================================================== Adapter: 0 Product Name: LSI MegaRAID SAS 9260-16i Memory: 512MB BBU: Present Serial No: [sERIAL NUMBER] ============================================================================== Number of DISK GROUPS: 1 DISK GROUP: 0 Number of Spans: 1 SPAN: 0 Span Reference: 0x00 Number of PDs: 12 Number of VDs: 1 Number of dedicated Hotspares: 0 Virtual Drive Information: Virtual Drive: 0 (Target Id: 0) Name :RAID5 RAID Level : Primary-5, Secondary-0, RAID Level Qualifier-3 Size : 40.019 TB Sector Size : 512 Is VD emulated : Yes Parity Size : 3.637 TB State : Optimal Strip Size : 256 KB Number Of Drives : 12 Span Depth : 1 Default Cache Policy: WriteBack, ReadAhead, Direct, No Write Cache if Bad BBU Current Cache Policy: WriteBack, ReadAhead, Direct, No Write Cache if Bad BBU Default Access Policy: Read/Write Current Access Policy: Read/Write Disk Cache Policy : Disk's Default Encryption Type : None Bad Blocks Exist: No Is VD Cached: No
Physical Disk Information:
Physical Disk: 0 Enclosure Device ID: 245 Slot Number: 0 Drive's position: DiskGroup: 0, Span: 0, Arm: 0 Enclosure position: N/A Device Id: 19 WWN: 50014ee20935345e Sequence Number: 2 Media Error Count: 0 Other Error Count: 0 Predictive Failure Count: 0 Last Predictive Failure Event Seq Number: 0 PD Type: SATA Raw Size: 3.638 TB [0x1d1c0beb0 Sectors] Non Coerced Size: 3.637 TB [0x1d1b0beb0 Sectors] Coerced Size: 3.637 TB [0x1d1b00000 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): 0x500062b2006259d0 Connected Port Number: 0(path0) Inquiry Data: WD-[sERIALNUMBER]WDC WD40EFRX-68WT0N0 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 :38C (100.40 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