#14741: High-memory usage during compilation using Template Haskell -------------------------------------+------------------------------------- Reporter: donatello | Owner: sighingnow Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.2.2 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Type of failure: Compile-time | Unknown/Multiple performance bug | Test Case: Blocked By: | Blocking: Related Tickets: #16190 | Differential Rev(s): Phab:D4384 Wiki Page: | -------------------------------------+------------------------------------- Comment (by hsyl20): I have made a patch to add an helper to TH to create "bytes" primitives: https://gitlab.haskell.org/hsyl20/ghc/tree/hsyl20-T14741 Using it we can patch `file-embed` like this: {{{ 19c19 < module Data.FileEmbed ---
module FileEmbed 49,53c49 < #if MIN_VERSION_template_haskell(2,5,0) < , Lit (StringL, StringPrimL, IntegerL) < #else < , Lit (StringL, IntegerL) < #endif
, Lit (..)
60a57
import Language.Haskell.TH 65a63 import qualified Data.ByteString.Internal as B 154c152,156 < #if MIN_VERSION_template_haskell(2, 8, 0)
#if MIN_VERSION_template_haskell(2, 15, 0) `AppE` LitE (bytesPrimL ( let B.PS ptr off sz = bs in mkBytes ptr (fromIntegral off) (fromIntegral sz)))) #elif MIN_VERSION_template_haskell(2, 8, 0) }}}
Using previous patches for #16198 and #16190, we get the following results when we embed a file of the given size: * V1: HEAD + patch for #16198 * V2: V1 + patch for #16190 (default threshold set to 500K) * V3: V2 + this patch || Size || 8.6.3 || V1 || V2 || V3 || Gain (V3 over v2) || || 128 || 2.650 || 2.331 || 2.346 || 2.291 || +2% || || 3K || 2.651 || 2.289 || 2.290 || 2.310 || -1% || || 30K || 2.590 || 2.353 || 2.307 || 2.299 || +0% || || 100K || 2.717 || 2.379 || 2.389 || 2.298 || +4% || || 500K || 3.621 || 2.814 || 2.331 || 2.315 || +1% || || 1M || 4.694 || 3.526 || 2.654 || 2.320 || +12% || || 2M || 6.784 || 4.668 || 2.650 || 2.350 || +11% || || 3M || 8.851 || 5.616 || 3.073 || 2.400 || +22% || || 30M || 63.181 || 34.318 || 8.517 || 3.390 || +60% || -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14741#comment:18 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler