Search results for query: PLP

  1. VictorSTS

    proxmox ceph performance with consumer grade samsung ssd

    ...hard to get more than ~40MBytes/s from each disk once the cache is full. Try to get your hands on some enterprise drives, specially due to their PLP which allows them to ack sync writes way faster and coalesce writes afterwards. Even second hand ones will serve you perfectly fine and last...
  2. V

    proxmox ceph performance with consumer grade samsung ssd

    ...straight to the SSDs. Even at low fill (∼10∼10), sustained RinRin above RfoldRfold produces multi‑second tails. Consumer QVOs also lack on‑drive PLP, so they can’t safely “ack” writes early; enterprise TLC SSDs with PLP keep TflushTflush in the O(1–10),msO(1–10),ms range under the same...
  3. J

    Ceph performance

    Lack of power-loss protection (PLP) on those SSDs is the primary reason for horrible IOPS. Read other posts on why PLP is important for SSDs. I get IOPS in the low thousands on a 7-node Ceph cluster using 10K RPM SAS drives on 16-drive bay nodes. For Ceph, more OSDs/nodes = more IOPS.
  4. leesteken

    Proxmox Nvme ZFS slow performance

    ...it's up to 3000 sequential but you are testing random/IOPS. If you want high sync writes (for fsync/sec like 10000) then use a drive that has PLP. Consumer drives are typically between 50 (which is like a HDD) and 250 (if I remember correctly). And ZFS does add overhead because all of the...
  5. Impact

    Fragen zu Ext4 vs ZFS

    ...-cPa zu testen. Es ist natürlich zu beachten, dass die Summe alleine nicht unbedingt das wichtigste ist und die Anzahl an Schreibvorgängen miteinzuberechnen ist. Write Amplification ist hier ein Thema und das kann durch PLP/Enterprise/DC SSDs und Dateisystem mehr oder weniger ausgeprägt sein.
  6. I

    Fragen zu Ext4 vs ZFS

    ...- geänderter ashift - RAIDZ ohne pool Geometrie und padding zu verstehen - geänderte volblocksize - extreme viele sync writes, die eigentlich auf PLP hätten sein sollen bei einem einfachen mirror && ashift = 12 && volblocksize 16k && VMs mit "normalem workload" frisst ZFS keine modernen...
  7. I

    Homeserver Rebuild

    ...damit ist man bereits auf der sicheren Seite. Will man es noch mehr optimieren, kann man zusätzlich - SWAP ändern oder deaktivieren - PLP SSD als SLOG hinzufügen - unterschiedliche volblocksizes verwenden - eventuell Daten wie logfiles mittels virtiofs auf datasets schreiben, statt auf vzvols
  8. B

    IO Backpressure, mein Fehler

    ...consumer-ssds sein müssen (kann nur abraten), dann schau wenigstens, dass es welche mit dram-cache sind und keine HMB-Laufwerke (die verwenden das system-ram als cache). beste performance mit zfs liefern natürlich laufwerke mit PLP, aber da gibts im consumer-bereich so gut wie keine mehr.
  9. leesteken

    The SSD search continues ...

    As a search will show: I have good experience with Micron 7450 PRO/MAX. They have PLP and are available with 1.92TB or 3.84TB of storage (110mm M.2). More options with SAS and U.2, U.3.
  10. N

    The SSD search continues ...

    ...Lenovo Enterprise 1.6TB MLC SATA 6Gbps Hot Swap Mainstream Endurance 3.5-inch Internal Solid State Drive (SSD) for x3250 M6, but im not seeing PLP or such yet. @leesteken: You're right, I'm down deep in the rabbit hole! I just want someone to tell me here is a 2TB PLP MLC (whatever) that...
  11. leesteken

    The SSD search continues ...

    ...flash as an SLC cache and that does not differentiate consumer/gamer drives from enterprise ones. Try to find SSDs with Power Loss Protection (PLP) as they can really speed up things and lower write amplification as they can cache (sync) writes. The exact type of flash memory then does not...
  12. SteveITS

    Ceph performance seems too slow

    Do some searching here or online about Proxmox/Ceph on consumer/non-PLP drives, they can make a big difference.
  13. leesteken

    Aid on Optimal Fresh Install

    ...are the exact opposite of getting high IOPS for active VM disks. Proxmox does not need an SSD for itself as speed is not important and it writes a lot (so and old HDD is fine). Maybe search the forum a bit about =1&c[nodes][0]=16&o=date']RAIDz1 and =1&c[nodes][0]=16&o=date']PLP to learn about...
  14. A

    Disk constellation for DXP4800

    See, I was right there with you till the word "drastically." Especially when that statement preceding was Please share your statistics backing "your rule." the word drastically has pretty substantial implications, and if the whole basis for your conclusion is "your feelings" you are not doing...
  15. UdoB

    Disk constellation for DXP4800

    Yes, a lot of setups will reach end of life before a cheap (non-PLP) SSD may die. At least you may hope for that. To increase the reliabilty drastically my rule is to use redundancy and to use "with-PLP" devices. Disclaimer: I do not follow my own rule everywhere, for the usual reasons...
  16. A

    Disk constellation for DXP4800

    Not sure where the connection between PLP and user scripts lie. wear out on any SSD made in the last 10 years is such a remote concern as to not warrant any thought at all. I bet you dont have a single SSD that is ANYWHERE CLOSE to wearout- I know I dont. I have SSDs in BUSY SERVERS with over 10...
  17. J

    Disk constellation for DXP4800

    ...have two options: Living with it and buying a new ssd from time to time (a ZFS mirror is really practical for it) or shopping for used ssds with PLP. The reason why I tend to recommend these options that I want to encourage people not to reilie on unsupported hacks or third-party scripts or...
  18. W

    Ceph: High Latency on NVMe SSD

    Thanks very much for Your replies! To proove the impact of missing PLP, I found a setting which is OFC NOT recommended for productive setup: /etc/ceph/ceph.conf bluestore_prefer_dm_nvme_plp = 0 It should make the thing perform, but it doesnt seem to have any effect. I couldnt find anything in...
  19. A

    Disk constellation for DXP4800

    ...more or less the same power, but nvmes consume more, otherwise just the smallest price per gig. Not this again. standard SSDs work JUST FINE. PLP is useful in situation where write performance is critical, and when you dont want the possibility of "last write" loss. for OP its not going to...
  20. N

    Disk constellation for DXP4800

    As an alternate opinion, I have self-hosted mail for over 30 years. I have used Exchange, Groupwise, Zimbra, SMail, plain PostFix annd even Sendmail. Most recently, I have been using MailCow. I find that SPAM is not a real problem if running SpamAssassiin or some similar tool. Frankly, I...