nix-super/src/libstore/binary-cache-store.hh
Eelco Dolstra 08ec757726
Make LocalBinaryCacheStore::narFromPath() run in constant memory
This reduces memory consumption of

  nix copy --from file://... --to ~/my-nix /nix/store/95cwv4q54dc6giaqv6q6p4r02ia2km35-blender-2.79

from 514 MiB to 18 MiB for an uncompressed binary cache, and from 192
MiB to 53 MiB for a bzipped binary cache. It may also be faster
because fetching can happen concurrently with decompression/writing.

Continuation of 48662d151b.

Issue https://github.com/NixOS/nix/issues/1681.
2018-05-30 13:34:57 +02:00

140 lines
3.9 KiB
C++

#pragma once
#include "crypto.hh"
#include "store-api.hh"
#include "pool.hh"
#include <atomic>
namespace nix {
struct NarInfo;
class BinaryCacheStore : public Store
{
public:
const Setting<std::string> compression{this, "xz", "compression", "NAR compression method ('xz', 'bzip2', or 'none')"};
const Setting<bool> writeNARListing{this, false, "write-nar-listing", "whether to write a JSON file listing the files in each NAR"};
const Setting<Path> secretKeyFile{this, "", "secret-key", "path to secret key used to sign the binary cache"};
const Setting<Path> localNarCache{this, "", "local-nar-cache", "path to a local cache of NARs"};
const Setting<bool> parallelCompression{this, false, "parallel-compression",
"enable multi-threading compression, available for xz only currently"};
private:
std::unique_ptr<SecretKey> secretKey;
protected:
BinaryCacheStore(const Params & params);
public:
virtual bool fileExists(const std::string & path) = 0;
virtual void upsertFile(const std::string & path,
const std::string & data,
const std::string & mimeType) = 0;
/* Note: subclasses must implement at least one of the two
following getFile() methods. */
/* Dump the contents of the specified file to a sink. */
virtual void getFile(const std::string & path, Sink & sink);
/* Fetch the specified file and call the specified callback with
the result. A subclass may implement this asynchronously. */
virtual void getFile(const std::string & path,
Callback<std::shared_ptr<std::string>> callback);
std::shared_ptr<std::string> getFile(const std::string & path);
protected:
bool wantMassQuery_ = false;
int priority = 50;
public:
virtual void init();
private:
std::string narMagic;
std::string narInfoFileFor(const Path & storePath);
void writeNarInfo(ref<NarInfo> narInfo);
public:
bool isValidPathUncached(const Path & path) override;
PathSet queryAllValidPaths() override
{ unsupported(); }
void queryPathInfoUncached(const Path & path,
Callback<std::shared_ptr<ValidPathInfo>> callback) override;
void queryReferrers(const Path & path,
PathSet & referrers) override
{ unsupported(); }
PathSet queryDerivationOutputs(const Path & path) override
{ unsupported(); }
StringSet queryDerivationOutputNames(const Path & path) override
{ unsupported(); }
Path queryPathFromHashPart(const string & hashPart) override
{ unsupported(); }
bool wantMassQuery() override { return wantMassQuery_; }
void addToStore(const ValidPathInfo & info, const ref<std::string> & nar,
RepairFlag repair, CheckSigsFlag checkSigs,
std::shared_ptr<FSAccessor> accessor) override;
Path addToStore(const string & name, const Path & srcPath,
bool recursive, HashType hashAlgo,
PathFilter & filter, RepairFlag repair) override;
Path addTextToStore(const string & name, const string & s,
const PathSet & references, RepairFlag repair) override;
void narFromPath(const Path & path, Sink & sink) override;
BuildResult buildDerivation(const Path & drvPath, const BasicDerivation & drv,
BuildMode buildMode) override
{ unsupported(); }
void ensurePath(const Path & path) override
{ unsupported(); }
void addTempRoot(const Path & path) override
{ unsupported(); }
void addIndirectRoot(const Path & path) override
{ unsupported(); }
Roots findRoots() override
{ unsupported(); }
void collectGarbage(const GCOptions & options, GCResults & results) override
{ unsupported(); }
ref<FSAccessor> getFSAccessor() override;
void addSignatures(const Path & storePath, const StringSet & sigs) override;
std::shared_ptr<std::string> getBuildLog(const Path & path) override;
int getPriority() override { return priority; }
};
MakeError(NoSuchBinaryCacheFile, Error);
}