# Block storage: EBS and ESSD > Capacity, IOPS, throughput, commitment, snapshots, and instance-channel limits for AWS EBS gp3 and Alibaba ESSD. --- LLMS index: [llms.txt](/llms.txt) --- > [!IMPORTANT] > **Snapshot:** 2026-08-22 · AWS `us-east-1` · Alibaba Cloud `cn-hangzhou` · > `1 USD = 6.7817 CNY`. Exact rates vary by region. The comparison aligns > provisioned capacity and requested IOPS/throughput, not latency or service level. ## Direct answer {#answer} “Price per GB” is not a valid block-storage comparison by itself. It can rank gp3 as cheaper at baseline and then reverse the answer once performance is matched. A usable bill must price at least four things: \[ \begin{aligned} \text{monthly block cost} ={}& \text{capacity} + \text{IOPS} + \text{throughput} \\ &+ \text{snapshots and recovery} + \text{network path} \end{aligned} \] The final usable performance is also bounded by the instance: \[ \text{usable I/O} = \min(\text{volume limit}, \text{instance storage-channel limit}) \] Paying for IOPS that the attached instance cannot deliver creates cost without performance. ## Two pricing philosophies {#philosophies} ### AWS EBS gp3: capacity and performance are explicit meters {#gp3} The snapshot uses: - Capacity: `$0.08/GB-month` (`¥0.5425`). - Included: `3,000 IOPS` and `125 MiB/s`. - Extra IOPS: `$0.005/IOPS-month`. - Extra throughput: `$0.04/MiB/s-month` in the exact `us-east-1` snapshot. So: \[ \begin{aligned} C_{gp3} ={}& 0.08G + 0.005\max(I-3000,0) \\ &+ 0.04\max(T-125,0) \end{aligned} \] All three are provisioned meters. Actual low usage does not refund unused provisioned IOPS or throughput. ### Alibaba ESSD: capacity often carries a performance curve {#essd} Traditional PL0–PL3 bind capacity to a product level. AutoPL separates capacity from optional provisioned and burst performance, but capacity still includes a rising baseline: \[ I_{base}=\max(\min(1800 + 50G, 50000), 3000) \] \[ T_{base}=\max(\min(120 + 0.5G, 350), 125) \] At 200 GiB this yields 11,800 IOPS and 220 MB/s; at 2,048 GiB the baseline reaches 50,000 IOPS and 350 MB/s. Alibaba's documentation also notes that the attached instance can impose the lower I/O ceiling. ## Capacity meter alone {#capacity} | Product | Capacity price | Included/baseline performance | PAYG-equivalent | 1 year | 3 years | 5 years | | --- | ---: | --- | ---: | ---: | ---: | ---: | | EBS gp3 | `¥0.5425/GiB-month` | 3K IOPS, 125 MiB/s | same list meter | contract-specific | contract-specific | contract-specific | | ESSD PL0 | `¥0.50/GiB-month` | capacity-coupled | `¥0.7665` | `¥0.425` | `¥0.25` | `¥0.25` | | ESSD PL1 / AutoPL | `¥1.00/GiB-month` | capacity-coupled to 50K / 350 | `¥1.533` | `¥0.85` | `¥0.50` | `¥0.50` | | ESSD PL2 | `¥2.00/GiB-month` | higher level; minimum 461 GiB | `¥3.066` | `¥1.70` | `¥1.00` | `¥1.00` | | ESSD PL3 | `¥4.00/GiB-month` | higher level; minimum 1,261 GiB | `¥6.132` | `¥3.40` | `¥2.00` | `¥2.00` | At this layer, gp3 is near PL0 and about 54% of PL1/AutoPL. That statement is true but incomplete. ## Performance-matched scenarios {#matched} | Capacity and target | EBS gp3 | ESSD AutoPL baseline | gp3 / AutoPL | Reading | | --- | ---: | ---: | ---: | --- | | 200 GiB · 3K IOPS · 125 MiB/s | `¥108.51/month` | `¥200.00/month` | `0.54×` | gp3 baseline is cheaper | | 200 GiB · 11.8K IOPS · 220 MiB/s | `¥432.67/month` | `¥200.00/month` | `2.16×` | AutoPL capacity baseline is cheaper | | 2,048 GiB · 50K IOPS · 350 MiB/s | `¥2,765.85/month` | `¥2,048.00/month` | `1.35×` | AutoPL remains cheaper at its baseline ceiling | This is the core block-storage insight: **the answer flips because one product charges extra performance separately while the other bundles a capacity-driven baseline.** It does not prove equal latency, durability, burst behavior, or instance delivery. The exact rows are in [`block_storage_scenarios.csv`](/data/cloud-pricing/2026-08-22-v1/tables/block_storage_scenarios.csv). ## What the price table still hides {#hidden} ### Snapshots and recovery {#snapshots} EBS snapshots bill changed blocks in S3-backed storage; cross-region copy, archive retrieval, fast snapshot restore, time-bounded copy, and provisioned initialization can add separate meters. ESSD snapshots, backup products, and cross-region recovery have their own lifecycle and transfer costs. A recovery budget needs restore time and restore throughput, not just snapshot GB-month. ### Topology and network {#topology} A single cloud disk is an availability-zone resource. Cross-AZ database or application topologies may duplicate volumes and add network charges. Managed database storage can price capacity, IOPS, and throughput at different markup factors from raw block storage. ### Provisioned versus consumed {#provisioned} Both capacity and performance can be paid before they are used. Track: - provisioned vs used GiB; - provisioned vs observed P95/P99 IOPS; - provisioned vs observed throughput; - instance channel utilization; - snapshot growth and orphan retention; - commitment coverage and unused term value. ## Extreme-performance layers {#extreme} At the high end, capacity is no longer the dominant meter. AWS io2 prices provisioned IOPS by volume-level tiers. Alibaba ESSD PL-X similarly separates capacity and IOPS; an official example for 2,048 GiB and two million IOPS totals `¥152,048/month`, of which `¥150,000` is performance. Low-end disks monetize capacity; high-end disks monetize performance. ## Historical insight {#history} AWS gp2 to gp3 reduced capacity price only 20%, from `$0.10` to `$0.08/GB-month`. For a 200 GiB volume, however, included baseline IOPS rose from 600 to 3,000, cutting price per baseline IOPS by 84%. Alibaba's 2016 SSD and 2026 ESSD PL1 both anchor at `¥1/GB-month`; performance, reliability, and product semantics improved while the capacity meter stayed flat. This is why “storage prices did not fall” and “storage price-performance improved sharply” can both be true. See [Cloud price history](/ledger/price-history/). ## A minimum bill worksheet {#worksheet} Before comparing disks, fill one row per volume: | Field | Required value | | --- | --- | | Region / AZ | Exact deployment path | | Provisioned and used capacity | GiB, both values | | IOPS | baseline, provisioned, P95/P99 observed | | Throughput | baseline, provisioned, P95/P99 observed | | Latency requirement | P50/P99 and block size | | Instance channel | max IOPS and throughput | | Snapshot and restore | changed GB, retention, RTO, copy path | | Topology | number of volumes, replicas, AZs | | Term | PAYG, monthly, 1/3/5 year, residual commitment | If any of these is missing, a capacity-price ratio is a lead, not a conclusion. ## Boundaries {#boundaries} - GB and GiB are retained exactly as providers publish them. - AutoPL baseline does not imply the attached instance can deliver it. - This comparison does not equalize latency, durability, burst, or SLA. - AWS rates are regional and tax-exclusive; Alibaba China-site rates are tax-inclusive. - Prices may have changed after 2026-08-22; refresh before purchase. ## Data and sources {#data} - [Block-storage rates](/data/cloud-pricing/2026-08-22-v1/tables/block_storage_rates.csv) - [Performance-matched scenarios](/data/cloud-pricing/2026-08-22-v1/tables/block_storage_scenarios.csv) - [Full pricing report](/data/cloud-pricing/2026-08-22-v1/report.md) - [Pricing source ledger](/data/cloud-pricing/2026-08-22-v1/tables/source_ledger.csv) - [Checksums](/data/cloud-pricing/2026-08-22-v1/checksums.txt) - [Original Chinese essay](https://vonng.com/cloud/ebs/)