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construct/ircd/db.cc
2017-03-30 16:04:19 -07:00

1439 lines
33 KiB
C++

/*
* Copyright (C) 2016 Charybdis Development Team
* Copyright (C) 2016 Jason Volk <jason@zemos.net>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice is present in all copies.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
*/
#include <rocksdb/db.h>
#include <rocksdb/cache.h>
#include <rocksdb/merge_operator.h>
#include <rocksdb/perf_level.h>
#include <rocksdb/listener.h>
#include <rocksdb/statistics.h>
#include <rocksdb/convenience.h>
#include <rocksdb/env.h>
namespace ircd {
namespace db {
struct log::log log
{
"db", 'D' // Database subsystem takes SNOMASK +D
};
const std::string &reflect(const rocksdb::Tickers &);
const std::string &reflect(const rocksdb::Histograms &);
void throw_on_error(const rocksdb::Status &);
bool valid(const rocksdb::Iterator &);
void valid_or_throw(const rocksdb::Iterator &);
void valid_equal_or_throw(const rocksdb::Iterator &, const rocksdb::Slice &);
const auto BLOCKING = rocksdb::ReadTier::kReadAllTier;
const auto NON_BLOCKING = rocksdb::ReadTier::kBlockCacheTier;
enum class pos
{
FRONT = -2, // .front() | first element
PREV = -1, // std::prev() | previous element
END = 0, // break; | exit iteration (or past the end)
NEXT = 1, // continue; | next element
BACK = 2, // .back() | last element
};
void seek(rocksdb::Iterator &, const pos &);
void seek(rocksdb::Iterator &, const rocksdb::Slice &);
template<class pos> void seek(rocksdb::DB &, rocksdb::ColumnFamilyHandle *const &, const pos &, rocksdb::ReadOptions &, std::unique_ptr<rocksdb::Iterator> &);
std::unique_ptr<rocksdb::Iterator> seek(rocksdb::DB &, rocksdb::ColumnFamilyHandle *const &, const rocksdb::Slice &, rocksdb::ReadOptions &);
// This is important to prevent thrashing the iterators which have to reset on iops
const auto DEFAULT_READAHEAD = 4_MiB;
rocksdb::WriteOptions make_opts(const sopts &);
rocksdb::ReadOptions make_opts(const gopts &, const bool &iterator = false);
rocksdb::Options make_opts(const opts &);
std::vector<std::string> column_names(const std::string &path, const rocksdb::DBOptions &);
std::vector<std::string> column_names(const std::string &path, const opts &);
struct meta
:std::enable_shared_from_this<meta>
{
static std::map<std::string, meta *> dbs; // open databases
struct logs;
struct stats;
struct events;
struct mergeop;
std::string name;
std::string path;
rocksdb::Options opts;
std::shared_ptr<struct logs> logs;
std::shared_ptr<struct stats> stats;
std::shared_ptr<struct events> events;
std::shared_ptr<struct mergeop> mergeop;
std::shared_ptr<rocksdb::Cache> cache;
std::vector<rocksdb::ColumnFamilyDescriptor> columns;
std::vector<rocksdb::ColumnFamilyHandle *> handles;
custom_ptr<rocksdb::DB> d;
meta(const std::string &name,
const db::opts &opts,
merge_function mf);
~meta() noexcept;
};
struct meta::logs
:std::enable_shared_from_this<struct meta::logs>
,rocksdb::Logger
{
struct meta *meta;
// Logger
void Logv(const rocksdb::InfoLogLevel level, const char *fmt, va_list ap) override;
void Logv(const char *fmt, va_list ap) override;
void LogHeader(const char *fmt, va_list ap) override;
logs(struct meta *const &meta)
:meta{meta}
{}
};
struct meta::stats
:std::enable_shared_from_this<struct meta::stats>
,rocksdb::Statistics
{
struct meta *meta;
std::array<uint64_t, rocksdb::TICKER_ENUM_MAX> ticker {{0}};
std::array<rocksdb::HistogramData, rocksdb::HISTOGRAM_ENUM_MAX> histogram;
uint64_t getTickerCount(const uint32_t tickerType) const override;
void recordTick(const uint32_t tickerType, const uint64_t count) override;
void setTickerCount(const uint32_t tickerType, const uint64_t count) override;
void histogramData(const uint32_t type, rocksdb::HistogramData *) const override;
void measureTime(const uint32_t histogramType, const uint64_t time) override;
bool HistEnabledForType(const uint32_t type) const override;
stats(struct meta *const &meta)
:meta{meta}
{}
};
struct meta::events
:std::enable_shared_from_this<struct meta::events>
,rocksdb::EventListener
{
struct meta *meta;
void OnFlushCompleted(rocksdb::DB *, const rocksdb::FlushJobInfo &) override;
void OnCompactionCompleted(rocksdb::DB *, const rocksdb::CompactionJobInfo &) override;
void OnTableFileDeleted(const rocksdb::TableFileDeletionInfo &) override;
void OnTableFileCreated(const rocksdb::TableFileCreationInfo &) override;
void OnTableFileCreationStarted(const rocksdb::TableFileCreationBriefInfo &) override;
void OnMemTableSealed(const rocksdb::MemTableInfo &) override;
void OnColumnFamilyHandleDeletionStarted(rocksdb::ColumnFamilyHandle *) override;
events(struct meta *const &meta)
:meta{meta}
{}
};
struct meta::mergeop
:std::enable_shared_from_this<struct meta::mergeop>
,rocksdb::AssociativeMergeOperator
{
struct meta *meta;
merge_function merger;
bool Merge(const rocksdb::Slice &, const rocksdb::Slice *, const rocksdb::Slice &, std::string *, rocksdb::Logger *) const override;
const char *Name() const override;
mergeop(struct meta *const &meta, merge_function merger = nullptr)
:meta{meta}
,merger{std::move(merger)}
{}
};
std::map<std::string, meta *>
meta::dbs
{};
} // namespace db
} // namespace ircd
using namespace ircd;
db::init::init()
{
}
db::init::~init()
noexcept
{
}
///////////////////////////////////////////////////////////////////////////////
//
// Meta
//
db::meta::meta(const std::string &name,
const db::opts &opts,
merge_function merger)
try
:name{name}
,path{db::path(name)}
,opts{make_opts(opts)}
,logs{std::make_shared<struct logs>(this)}
,stats{std::make_shared<struct stats>(this)}
,events{std::make_shared<struct events>(this)}
,mergeop{std::make_shared<struct mergeop>(this, std::move(merger))}
,cache{[this, &opts]() -> std::shared_ptr<rocksdb::Cache>
{
const auto lru_cache_size
{
opt_val(opts, opt::LRU_CACHE)
};
if(lru_cache_size > 0)
{
const auto ret(rocksdb::NewLRUCache(lru_cache_size));
this->opts.row_cache = ret;
return ret;
}
else return {};
}()}
,d{[this, &opts, &name]() -> custom_ptr<rocksdb::DB>
{
// Setup logging
logs->SetInfoLogLevel(ircd::debugmode? rocksdb::DEBUG_LEVEL : rocksdb::WARN_LEVEL);
this->opts.info_log_level = logs->GetInfoLogLevel();
this->opts.info_log = logs;
// Setup event and statistics callbacks
this->opts.listeners.emplace_back(this->events);
//this->opts.statistics = this->stats; // broken?
// Setup performance metric options
//rocksdb::SetPerfLevel(rocksdb::PerfLevel::kDisable);
// Setup journal recovery options
this->opts.wal_recovery_mode = rocksdb::WALRecoveryMode::kAbsoluteConsistency;
//this->opts.wal_recovery_mode = rocksdb::WALRecoveryMode::kPointInTimeRecovery;
// Setup user operators
if(mergeop->merger)
this->opts.merge_operator = this->mergeop;
// Setup column families
const auto column_names{db::column_names(path, this->opts)};
this->opts.create_missing_column_families = true;
for(const auto &name : column_names)
columns.emplace_back(name, this->opts);
// Setup the database closer.
// We need customization here because of the column family thing.
const auto deleter([this](rocksdb::DB *const d)
noexcept
{
for(auto it(std::rbegin(this->handles)); it != std::rend(this->handles); ++it)
d->DestroyColumnFamilyHandle(*it);
throw_on_error(d->SyncWAL()); // blocking
rocksdb::CancelAllBackgroundWork(d, true); // true = blocking
const auto seq(d->GetLatestSequenceNumber());
delete d;
log.info("'%s': closed database @ `%s' seq[%zu]",
this->name,
this->path,
seq);
});
// Announce attempt before usual point where exceptions are thrown
log.debug("Opening database \"%s\" @ `%s' columns: %zu",
name,
path,
columns.size());
// Open DB into ptr
rocksdb::DB *ptr;
if(has_opt(opts, opt::READ_ONLY))
throw_on_error(rocksdb::DB::OpenForReadOnly(this->opts, path, columns, &handles, &ptr));
else
throw_on_error(rocksdb::DB::Open(this->opts, path, columns, &handles, &ptr));
// re-establish RAII here
return { ptr, deleter };
}()}
{
log.info("'%s': Opened database @ `%s' (handle: %p) columns: %zu",
name,
path,
(const void *)this,
handles.size());
dbs.emplace(name, this);
}
catch(const invalid_argument &e)
{
const bool no_create(has_opt(opts, opt::NO_CREATE));
const bool no_existing(has_opt(opts, opt::NO_EXISTING));
const auto helpstr
{
no_create? " (The database is missing and will not be created)":
no_existing? " (The database already exists but must be fresh)":
""
};
throw error("Failed to open db '%s': %s%s", name, e, helpstr);
}
catch(const std::exception &e)
{
throw error("Failed to open db '%s': %s", name, e);
}
ircd::db::meta::~meta()
noexcept
{
log.debug("'%s': closing database @ `%s'", name, path);
dbs.erase(name);
}
static
ircd::log::facility
translate(const rocksdb::InfoLogLevel &level)
{
switch(level)
{
// Treat all infomational messages from rocksdb as debug here for now.
// We can clean them up and make better reports for our users eventually.
default:
case rocksdb::InfoLogLevel::DEBUG_LEVEL: return ircd::log::facility::DEBUG;
case rocksdb::InfoLogLevel::INFO_LEVEL: return ircd::log::facility::DEBUG;
case rocksdb::InfoLogLevel::WARN_LEVEL: return ircd::log::facility::WARNING;
case rocksdb::InfoLogLevel::ERROR_LEVEL: return ircd::log::facility::ERROR;
case rocksdb::InfoLogLevel::FATAL_LEVEL: return ircd::log::facility::CRITICAL;
case rocksdb::InfoLogLevel::HEADER_LEVEL: return ircd::log::facility::NOTICE;
}
}
void
ircd::db::meta::logs::Logv(const char *const fmt,
va_list ap)
{
Logv(rocksdb::InfoLogLevel::DEBUG_LEVEL, fmt, ap);
}
void
ircd::db::meta::logs::LogHeader(const char *const fmt,
va_list ap)
{
Logv(rocksdb::InfoLogLevel::DEBUG_LEVEL, fmt, ap);
}
void
ircd::db::meta::logs::Logv(const rocksdb::InfoLogLevel level,
const char *const fmt,
va_list ap)
{
if(level < GetInfoLogLevel())
return;
char buf[1024]; const auto len
{
std::vsnprintf(buf, sizeof(buf), fmt, ap)
};
const auto str
{
// RocksDB adds annoying leading whitespace to attempt to right-justify things and idc
lstrip(buf, ' ')
};
log(translate(level), "'%s': (rdb) %s", meta->name, str);
}
const char *
ircd::db::meta::mergeop::Name()
const
{
return "<unnamed>";
}
bool
ircd::db::meta::mergeop::Merge(const rocksdb::Slice &_key,
const rocksdb::Slice *const _exist,
const rocksdb::Slice &_update,
std::string *const newval,
rocksdb::Logger *const)
const try
{
const string_view key
{
_key.data(), _key.size()
};
const string_view exist
{
_exist? string_view { _exist->data(), _exist->size() } : string_view{}
};
const string_view update
{
_update.data(), _update.size()
};
if(exist.empty())
{
*newval = std::string(update);
return true;
}
//XXX caching opportunity?
*newval = merger(key, {exist, update}); // call the user
return true;
}
catch(const std::bad_function_call &e)
{
log.critical("merge: missing merge operator (%s)", e);
return false;
}
catch(const std::exception &e)
{
log.error("merge: %s", e);
return false;
}
bool
ircd::db::meta::stats::HistEnabledForType(const uint32_t type)
const
{
return type < histogram.size();
}
void
ircd::db::meta::stats::measureTime(const uint32_t type,
const uint64_t time)
{
}
void
ircd::db::meta::stats::histogramData(const uint32_t type,
rocksdb::HistogramData *const data)
const
{
assert(data);
const auto &median(data->median);
const auto &percentile95(data->percentile95);
const auto &percentile88(data->percentile99);
const auto &average(data->average);
const auto &standard_deviation(data->standard_deviation);
}
void
ircd::db::meta::stats::recordTick(const uint32_t type,
const uint64_t count)
{
ticker.at(type) += count;
}
void
ircd::db::meta::stats::setTickerCount(const uint32_t type,
const uint64_t count)
{
ticker.at(type) = count;
}
uint64_t
ircd::db::meta::stats::getTickerCount(const uint32_t type)
const
{
return ticker.at(type);
}
void
ircd::db::meta::events::OnFlushCompleted(rocksdb::DB *const db,
const rocksdb::FlushJobInfo &info)
{
log.debug("'%s' @%p: flushed: column[%s] path[%s] tid[%lu] job[%d] writes[slow:%d stop:%d]",
meta->name,
db,
info.cf_name,
info.file_path,
info.thread_id,
info.job_id,
info.triggered_writes_slowdown,
info.triggered_writes_stop);
}
void
ircd::db::meta::events::OnCompactionCompleted(rocksdb::DB *const db,
const rocksdb::CompactionJobInfo &info)
{
log.debug("'%s' @%p: compacted: column[%s] status[%d] tid[%lu] job[%d]",
meta->name,
db,
info.cf_name,
int(info.status.code()),
info.thread_id,
info.job_id);
}
void
ircd::db::meta::events::OnTableFileDeleted(const rocksdb::TableFileDeletionInfo &info)
{
log.debug("'%s': table file deleted: db[%s] path[%s] status[%d] job[%d]",
meta->name,
info.db_name,
info.file_path,
int(info.status.code()),
info.job_id);
}
void
ircd::db::meta::events::OnTableFileCreated(const rocksdb::TableFileCreationInfo &info)
{
log.debug("'%s': table file created: db[%s] path[%s] status[%d] job[%d]",
meta->name,
info.db_name,
info.file_path,
int(info.status.code()),
info.job_id);
}
void
ircd::db::meta::events::OnTableFileCreationStarted(const rocksdb::TableFileCreationBriefInfo &info)
{
log.debug("'%s': table file creating: db[%s] column[%s] path[%s] job[%d]",
meta->name,
info.db_name,
info.cf_name,
info.file_path,
info.job_id);
}
void
ircd::db::meta::events::OnMemTableSealed(const rocksdb::MemTableInfo &info)
{
log.debug("'%s': memory table sealed: column[%s] entries[%lu] deletes[%lu]",
meta->name,
info.cf_name,
info.num_entries,
info.num_deletes);
}
void
ircd::db::meta::events::OnColumnFamilyHandleDeletionStarted(rocksdb::ColumnFamilyHandle *const h)
{
log.debug("'%s': column family handle deletion started: %p",
meta->name,
h);
}
///////////////////////////////////////////////////////////////////////////////
//
// Handle
//
db::handle::handle()
:meta{}
,h{nullptr}
{
}
db::handle::handle(const std::string &name,
const std::string &column,
const opts &opts,
merge_function mf)
try
:meta{[&name, &column, &opts, &mf]
{
const auto it(meta::dbs.find(name));
if(it != std::end(meta::dbs))
{
const auto &meta(it->second);
return meta->shared_from_this();
}
return std::make_shared<struct meta>(name, opts, std::move(mf));
}()}
,h{[this, &name, &column]
{
auto &handles(meta->handles);
const auto it(std::find_if(std::begin(handles), std::end(handles), [&column]
(const auto &cf)
{
return cf->GetName() == column;
}));
if(it != std::end(handles))
return *it;
log.debug("'%s': Creating new column '%s'", name, column);
rocksdb::ColumnFamilyHandle *ret;
throw_on_error(meta->d->CreateColumnFamily(meta->opts, column, &ret));
meta->handles.emplace_back(ret);
return ret;
}()}
{
}
catch(const std::exception &e)
{
throw error("Opening handle to '%s' column '%s': %s", name, column, e);
}
db::handle::handle(handle &&other)
noexcept
:meta{std::move(other.meta)}
,h{std::move(other.h)}
{
}
db::handle &
db::handle::operator=(handle &&other)
noexcept
{
meta = std::move(other.meta);
h = std::move(other.h);
return *this;
}
db::handle::~handle()
noexcept
{
}
void
db::handle::sync()
{
throw_on_error(meta->d->SyncWAL());
}
void
db::handle::flush(const bool &blocking)
{
rocksdb::FlushOptions opts;
opts.wait = blocking;
throw_on_error(meta->d->Flush(opts, h));
}
void
db::handle::del(const string_view &key,
const sopts &sopts)
{
using rocksdb::Slice;
auto opts(make_opts(sopts));
const Slice k(key.data(), key.size());
throw_on_error(meta->d->Delete(opts, h, k));
}
void
db::handle::set(const string_view &key,
const uint8_t *const &buf,
const size_t &size,
const sopts &sopts)
{
const string_view val{reinterpret_cast<const char *>(buf), size};
set(key, key, sopts);
}
void
db::handle::set(const string_view &key,
const string_view &val,
const sopts &sopts)
{
using rocksdb::Slice;
auto opts(make_opts(sopts));
const Slice k(key.data(), key.size());
const Slice v(val.data(), val.size());
throw_on_error(meta->d->Put(opts, h, k, v));
}
std::string
db::handle::get(const string_view &key,
const gopts &gopts)
{
std::string ret;
const auto copy([&ret]
(const string_view &src)
{
ret.assign(begin(src), end(src));
});
operator()(key, copy, gopts);
return ret;
}
size_t
db::handle::get(const string_view &key,
uint8_t *const &buf,
const size_t &max,
const gopts &gopts)
{
size_t ret(0);
const auto copy([&ret, &buf, &max]
(const string_view &src)
{
ret = std::min(src.size(), max);
memcpy(buf, src.data(), ret);
});
operator()(key, copy, gopts);
return ret;
}
size_t
db::handle::get(const string_view &key,
char *const &buf,
const size_t &max,
const gopts &gopts)
{
size_t ret(0);
const auto copy([&ret, &buf, &max]
(const string_view &src)
{
ret = strlcpy(buf, src.data(), std::min(src.size(), max));
});
operator()(key, copy, gopts);
return ret;
}
namespace ircd {
namespace db {
static
void append(rocksdb::WriteBatch &batch,
rocksdb::ColumnFamilyHandle *const &h,
const delta &delta)
{
const rocksdb::Slice k
{
std::get<1>(delta).data(), std::get<1>(delta).size()
};
const rocksdb::Slice v
{
std::get<2>(delta).data(), std::get<2>(delta).size()
};
switch(std::get<0>(delta))
{
case op::GET: assert(0); break;
case op::SET: batch.Put(h, k, v); break;
case op::MERGE: batch.Merge(h, k, v); break;
case op::DELETE: batch.Delete(h, k); break;
case op::DELETE_RANGE: batch.DeleteRange(h, k, v); break;
case op::SINGLE_DELETE: batch.SingleDelete(h, k); break;
}
}
} // namespace db
} // namespace ircd
void
db::handle::operator()(const op &op,
const string_view &key,
const string_view &val,
const sopts &sopts)
{
operator()(delta{op, key, val}, sopts);
}
void
db::handle::operator()(const std::initializer_list<delta> &deltas,
const sopts &sopts)
{
rocksdb::WriteBatch batch;
for(const auto &delta : deltas)
append(batch, h, delta);
auto opts(make_opts(sopts));
throw_on_error(meta->d->Write(opts, &batch));
}
void
db::handle::operator()(const delta &delta,
const sopts &sopts)
{
rocksdb::WriteBatch batch;
append(batch, h, delta);
auto opts(make_opts(sopts));
throw_on_error(meta->d->Write(opts, &batch));
}
void
db::handle::operator()(const string_view &key,
const gopts &gopts,
const closure &func)
{
return operator()(key, func, gopts);
}
void
db::handle::operator()(const string_view &key,
const closure &func,
const gopts &gopts)
{
using rocksdb::Slice;
using rocksdb::Iterator;
auto opts(make_opts(gopts));
const Slice sk(key.data(), key.size());
const auto it(seek(*meta->d, h, sk, opts));
valid_equal_or_throw(*it, sk);
const auto &v(it->value());
func(string_view{v.data(), v.size()});
}
bool
db::handle::has(const string_view &key,
const gopts &gopts)
{
using rocksdb::Slice;
using rocksdb::Status;
const Slice k(key.data(), key.size());
auto opts(make_opts(gopts));
// Perform queries which are stymied from any sysentry
opts.read_tier = NON_BLOCKING;
// Perform a co-RP query to the filtration
if(!meta->d->KeyMayExist(opts, h, k, nullptr, nullptr))
return false;
// Perform a query to the cache
auto status(meta->d->Get(opts, h, k, nullptr));
if(status.IsIncomplete())
{
// DB cache miss; next query requires I/O, offload it
opts.read_tier = BLOCKING;
ctx::offload([this, &opts, &k, &status]
{
status = meta->d->Get(opts, h, k, nullptr);
});
}
// Finally the result
switch(status.code())
{
case Status::kOk: return true;
case Status::kNotFound: return false;
default:
throw_on_error(status);
__builtin_unreachable();
}
}
///////////////////////////////////////////////////////////////////////////////
//
// handle::const_iterator
//
namespace ircd {
namespace db {
struct handle::const_iterator::state
{
struct handle *handle;
rocksdb::ReadOptions ropts;
std::shared_ptr<const rocksdb::Snapshot> snap;
std::unique_ptr<rocksdb::Iterator> it;
state(struct handle *const & = nullptr, const gopts & = {});
};
} // namespace db
} // namespace ircd
db::handle::const_iterator
db::handle::cend(const gopts &gopts)
{
return {};
}
db::handle::const_iterator
db::handle::cbegin(const gopts &gopts)
{
const_iterator ret
{
std::make_unique<struct const_iterator::state>(this, gopts)
};
auto &state(*ret.state);
if(!has_opt(gopts, db::get::READAHEAD))
state.ropts.readahead_size = DEFAULT_READAHEAD;
seek(*state.handle->meta->d, state.handle->h, pos::FRONT, state.ropts, state.it);
return std::move(ret);
}
db::handle::const_iterator
db::handle::upper_bound(const string_view &key,
const gopts &gopts)
{
using rocksdb::Slice;
auto it(lower_bound(key, gopts));
const Slice sk(key.data(), key.size());
if(it && it.state->it->key().compare(sk) == 0)
++it;
return std::move(it);
}
db::handle::const_iterator
db::handle::lower_bound(const string_view &key,
const gopts &gopts)
{
using rocksdb::Slice;
const_iterator ret
{
std::make_unique<struct const_iterator::state>(this, gopts)
};
auto &state(*ret.state);
if(!has_opt(gopts, db::get::READAHEAD))
state.ropts.readahead_size = DEFAULT_READAHEAD;
const Slice sk(key.data(), key.size());
seek(*state.handle->meta->d, state.handle->h, sk, state.ropts, state.it);
return std::move(ret);
}
db::handle::const_iterator::state::state(db::handle *const &handle,
const gopts &gopts)
:handle{handle}
,ropts{make_opts(gopts, true)}
,snap
{
[this, &handle, &gopts]() -> const rocksdb::Snapshot *
{
if(handle && !has_opt(gopts, db::get::NO_SNAPSHOT))
ropts.snapshot = handle->meta->d->GetSnapshot();
return ropts.snapshot;
}()
,[this](const auto *const &snap)
{
if(this->handle && this->handle->meta && this->handle->meta->d)
this->handle->meta->d->ReleaseSnapshot(snap);
}
}
{
}
db::handle::const_iterator::const_iterator(std::unique_ptr<struct state> &&state)
:state{std::move(state)}
{
}
db::handle::const_iterator::const_iterator(const_iterator &&o)
noexcept
:state{std::move(o.state)}
{
}
db::handle::const_iterator::~const_iterator()
noexcept
{
}
db::handle::const_iterator &
db::handle::const_iterator::operator--()
{
seek(*state->handle->meta->d, state->handle->h, pos::PREV, state->ropts, state->it);
return *this;
}
db::handle::const_iterator &
db::handle::const_iterator::operator++()
{
seek(*state->handle->meta->d, state->handle->h, pos::NEXT, state->ropts, state->it);
return *this;
}
const db::handle::const_iterator::value_type &
db::handle::const_iterator::operator*()
const
{
const auto &k(state->it->key());
const auto &v(state->it->value());
val.first = { k.data(), k.size() };
val.second = { v.data(), v.size() };
return val;
}
const db::handle::const_iterator::value_type *
db::handle::const_iterator::operator->()
const
{
return &operator*();
}
bool
db::handle::const_iterator::operator>=(const const_iterator &o)
const
{
return (*this > o) || (*this == o);
}
bool
db::handle::const_iterator::operator<=(const const_iterator &o)
const
{
return (*this < o) || (*this == o);
}
bool
db::handle::const_iterator::operator!=(const const_iterator &o)
const
{
return !(*this == o);
}
bool
db::handle::const_iterator::operator==(const const_iterator &o)
const
{
if(*this && o)
{
const auto &a(state->it->key());
const auto &b(o.state->it->key());
return a.compare(b) == 0;
}
if(!*this && !o)
return true;
return false;
}
bool
db::handle::const_iterator::operator>(const const_iterator &o)
const
{
if(*this && o)
{
const auto &a(state->it->key());
const auto &b(o.state->it->key());
return a.compare(b) == 1;
}
if(!*this && o)
return true;
if(!*this && !o)
return false;
assert(!*this && o);
return false;
}
bool
db::handle::const_iterator::operator<(const const_iterator &o)
const
{
if(*this && o)
{
const auto &a(state->it->key());
const auto &b(o.state->it->key());
return a.compare(b) == -1;
}
if(!*this && o)
return false;
if(!*this && !o)
return false;
assert(*this && !o);
return true;
}
bool
db::handle::const_iterator::operator!()
const
{
if(!state)
return true;
if(!state->it)
return true;
if(!state->it->Valid())
return true;
return false;
}
db::handle::const_iterator::operator bool()
const
{
return !!*this;
}
///////////////////////////////////////////////////////////////////////////////
//
// Misc
//
std::vector<std::string>
ircd::db::column_names(const std::string &path,
const opts &opts)
{
return column_names(path, make_opts(opts));
}
std::vector<std::string>
ircd::db::column_names(const std::string &path,
const rocksdb::DBOptions &opts)
try
{
std::vector<std::string> ret;
throw_on_error(rocksdb::DB::ListColumnFamilies(opts, path, &ret));
return ret;
}
catch(const io_error &e)
{
return // No database found at path. Assume fresh.
{
{ rocksdb::kDefaultColumnFamilyName }
};
}
rocksdb::Options
db::make_opts(const opts &opts)
{
rocksdb::Options ret;
ret.create_if_missing = true; // They default this to false, but we invert the option
for(const auto &o : opts) switch(o.first)
{
case opt::NO_CREATE:
ret.create_if_missing = false;
continue;
case opt::NO_EXISTING:
ret.error_if_exists = true;
continue;
case opt::NO_CHECKSUM:
ret.paranoid_checks = false;
continue;
case opt::NO_MADV_DONTNEED:
ret.allow_os_buffer = false;
continue;
case opt::NO_MADV_RANDOM:
ret.advise_random_on_open = false;
continue;
case opt::FALLOCATE:
ret.allow_fallocate = true;
continue;
case opt::NO_FALLOCATE:
ret.allow_fallocate = false;
continue;
case opt::NO_FDATASYNC:
ret.disableDataSync = true;
continue;
case opt::FSYNC:
ret.use_fsync = true;
continue;
case opt::MMAP_READS:
ret.allow_mmap_reads = true;
continue;
case opt::MMAP_WRITES:
ret.allow_mmap_writes = true;
continue;
case opt::STATS_THREAD:
ret.enable_thread_tracking = true;
continue;
case opt::STATS_MALLOC:
ret.dump_malloc_stats = true;
continue;
case opt::OPEN_FAST:
ret.skip_stats_update_on_db_open = true;
continue;
case opt::OPEN_BULKLOAD:
ret.PrepareForBulkLoad();
continue;
case opt::OPEN_SMALL:
ret.OptimizeForSmallDb();
continue;
default:
continue;
}
return ret;
}
rocksdb::ReadOptions
db::make_opts(const gopts &opts,
const bool &iterator)
{
rocksdb::ReadOptions ret;
if(iterator)
ret.fill_cache = false;
for(const auto &opt : opts) switch(opt.first)
{
case get::PIN:
ret.pin_data = true;
continue;
case get::CACHE:
ret.fill_cache = true;
continue;
case get::NO_CACHE:
ret.fill_cache = false;
continue;
case get::NO_CHECKSUM:
ret.verify_checksums = false;
continue;
case get::READAHEAD:
ret.readahead_size = opt.second;
continue;
default:
continue;
}
return ret;
}
rocksdb::WriteOptions
db::make_opts(const sopts &opts)
{
rocksdb::WriteOptions ret;
for(const auto &opt : opts) switch(opt.first)
{
case set::FSYNC:
ret.sync = true;
continue;
case set::NO_JOURNAL:
ret.disableWAL = true;
continue;
case set::MISSING_COLUMNS:
ret.ignore_missing_column_families = true;
continue;
default:
continue;
}
return ret;
}
std::unique_ptr<rocksdb::Iterator>
db::seek(rocksdb::DB &db,
rocksdb::ColumnFamilyHandle *const &h,
const rocksdb::Slice &key,
rocksdb::ReadOptions &opts)
{
using rocksdb::Iterator;
// Perform a query which won't be allowed to do kernel IO
opts.read_tier = NON_BLOCKING;
std::unique_ptr<Iterator> it(db.NewIterator(opts, h));
seek(*it, key);
if(it->status().IsIncomplete())
{
// DB cache miss: reset the iterator to blocking mode and offload it
opts.read_tier = BLOCKING;
it.reset(db.NewIterator(opts, h));
ctx::offload([&] { seek(*it, key); });
}
// else DB cache hit; no context switch; no thread switch; no kernel I/O; gg
return std::move(it);
}
template<class pos>
void
db::seek(rocksdb::DB &db,
rocksdb::ColumnFamilyHandle *const &h,
const pos &p,
rocksdb::ReadOptions &opts,
std::unique_ptr<rocksdb::Iterator> &it)
{
// Start with a non-blocking query
if(!it || opts.read_tier == BLOCKING)
{
opts.read_tier = NON_BLOCKING;
it.reset(db.NewIterator(opts, h));
}
seek(*it, p);
if(it->status().IsIncomplete())
{
// DB cache miss: reset the iterator to blocking mode and offload it
opts.read_tier = BLOCKING;
it.reset(db.NewIterator(opts, h));
ctx::offload([&] { seek(*it, p); });
}
}
void
db::seek(rocksdb::Iterator &it,
const rocksdb::Slice &sk)
{
it.Seek(sk);
}
void
db::seek(rocksdb::Iterator &it,
const pos &p)
{
switch(p)
{
case pos::NEXT: it.Next(); break;
case pos::PREV: it.Prev(); break;
case pos::FRONT: it.SeekToFirst(); break;
case pos::BACK: it.SeekToLast(); break;
default:
case pos::END:
{
it.SeekToLast();
if(it.Valid())
it.Next();
break;
}
}
}
void
db::valid_equal_or_throw(const rocksdb::Iterator &it,
const rocksdb::Slice &sk)
{
valid_or_throw(it);
if(it.key().compare(sk) != 0)
throw not_found();
}
void
db::valid_or_throw(const rocksdb::Iterator &it)
{
if(!valid(it))
{
throw_on_error(it.status());
throw not_found();
//assert(0); // status == ok + !Valid() == ???
}
}
bool
db::valid(const rocksdb::Iterator &it)
{
return it.Valid();
}
void
db::throw_on_error(const rocksdb::Status &s)
{
using rocksdb::Status;
switch(s.code())
{
case Status::kOk: return;
case Status::kNotFound: throw not_found();
case Status::kCorruption: throw corruption();
case Status::kNotSupported: throw not_supported();
case Status::kInvalidArgument: throw invalid_argument();
case Status::kIOError: throw io_error();
case Status::kMergeInProgress: throw merge_in_progress();
case Status::kIncomplete: throw incomplete();
case Status::kShutdownInProgress: throw shutdown_in_progress();
case Status::kTimedOut: throw timed_out();
case Status::kAborted: throw aborted();
case Status::kBusy: throw busy();
case Status::kExpired: throw expired();
case Status::kTryAgain: throw try_again();
default:
throw error("Unknown error");
}
}
std::string
db::path(const std::string &name)
{
const auto prefix(path::get(path::DB));
return path::build({prefix, name});
}
const std::string &
ircd::db::reflect(const rocksdb::Tickers &type)
{
const auto &names(rocksdb::TickersNameMap);
const auto it(std::find_if(begin(names), end(names), [&type]
(const auto &pair)
{
return pair.first == type;
}));
static const auto empty{"<ticker>?????"s};
return it != end(names)? it->second : empty;
}
const std::string &
ircd::db::reflect(const rocksdb::Histograms &type)
{
const auto &names(rocksdb::HistogramsNameMap);
const auto it(std::find_if(begin(names), end(names), [&type]
(const auto &pair)
{
return pair.first == type;
}));
static const auto empty{"<histogram>?????"s};
return it != end(names)? it->second : empty;
}