r - mclapply 与 lme4 和长向量

Question

我正在使用 parallel 包中的 mclapply 来估计在高性能集群上使用 lme4 包的混合 glmer 模型。我遇到问题 described here 。我应用了添加 mc.preschedule=F 的建议修复，但问题仍然存在。代码设置为described here .

我不知道如何解决这个问题，有什么想法吗？我应该切换到另一种并行化方法吗？如果是这样，怎么办？

这是我的代码，但基本上它遵循链接文章的逻辑:

rm(list = ls())

require(lme4)
require(parallel)

load(file="//share//home//eborbath//ess_rescaled.Rda") # load data

# paralelizing function

f_lmer_mc = function(data, calls, mc.cores) {
  require(parallel)
  if (is.data.frame(data)) 
    data = replicate(length(calls), data, simplify = F)
  for (i in 1:length(data)) attr(data[[i]], "cll") = calls[i]
  m.list = mclapply(data, function(i) eval(parse(text = attr(i, "cll"))), 
                    mc.cores = mc.cores, mc.preschedule = FALSE)
  return(m.list)
}

##########
# Models #
##########


controls <- c("gender", "agea", "eduyrs", "domicil", "unemployed", "rideol", "union", "pid", "hincfel")
values <- c("conformity", "universalism", "security")
issues <- c("gincdif", "freehms")
agr.ctrl <- c("gdp_wb_ppp", "wb_vae")
lr.agr <- c("lr_rsquar_std", "ri_l2_std")
val.agr <- c("mean_univ", "mean_conf", "mean_secur")
end <- "1 + (1|cntry/countryyear), data=i, control=glmerControl(optimizer='bobyqa', optCtrl = list(maxfun = 1e9)), family=binomial(link='logit'))"

models = c(paste0("glmer(protest ~", paste(c(controls, end), collapse="+")),
paste0("glmer(protest ~", paste(c(controls, values, end), collapse="+")),
paste0("glmer(protest ~", paste(c(controls, values, issues, end), collapse="+")),
paste0("glmer(protest ~ region+", paste(c(controls, values, issues, end), collapse="+")),
paste0("glmer(protest ~ region+", paste(c(controls, values, issues, agr.ctrl, end), collapse="+")), 
paste0("glmer(protest ~ region+", paste(c(controls, values, issues, agr.ctrl, lr.agr, end), collapse="+")),
paste0("glmer(protest ~ region+", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")), # until here it's only main effects
paste0("glmer(protest ~ region*rideol + region+", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")), 
paste0("glmer(protest ~ region*rideol*year + region+year+", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")), 
paste0("glmer(protest ~ region*rideol*year_num + region+year_num+", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")), 
paste0("glmer(protest ~ region*soc_pop_eleches + region+soc_pop_eleches+", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")), # now come the expl. models
paste0("glmer(protest ~ region*rideol*soc_pop_eleches + region+soc_pop_eleches+", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")),
paste0("glmer(protest ~ region*ri_l2_std + region+", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")),
paste0("glmer(protest ~ region*ri_l2_std*rideol + region+", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")),
paste0("glmer(protest ~ region*lr_rsquar_std + region+", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")),
paste0("glmer(protest ~ region*lr_rsquar_std*rideol + region+", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")),
paste0("glmer(protest ~ region+gov_genlr", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")),
paste0("glmer(protest ~ region*gov_genlr + region+gov_genlr", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")),
paste0("glmer(protest ~ region*gov_genlr*rideol + region+gov_genlr", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")),
paste0("glmer(protest ~ region+pol_lrecon", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")),
paste0("glmer(protest ~ region+pol_galtan", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")),
paste0("glmer(protest ~ region+pol_galtan+pol_lrecon", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")),
paste0("glmer(protest ~ region*pol_lrecon+region+pol_galtan+pol_lrecon", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")),
paste0("glmer(protest ~ region*pol_galtan+region+pol_galtan+pol_lrecon", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")),
paste0("glmer(protest ~ region*pol_lrecon*rideol+region+pol_galtan+pol_lrecon", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")),
paste0("glmer(protest ~ region*pol_galtan*rideol+region+pol_galtan+pol_lrecon", paste(c(controls, values, issues, agr.ctrl, lr.agr, val.agr, end), collapse="+")))

m.list = f_lmer_mc(data, models, 24)

m.1 <- c(m.list[1:3])
m.2 <- c(m.list[4:6])
m.3 <- c(m.list[7:9])
m.4 <- c(m.list[10:12])
m.5 <- c(m.list[13:15])
m.6 <- c(m.list[16:18])
m.7 <- c(m.list[19:21])
m.8 <- c(m.list[22:24])
m.9 <- c(m.list[25:26])

save(m.1, data, file='m_1.RData')
save(m.2, data, file='m_2.RData')
save(m.3, data, file='m_3.RData')
save(m.4, data, file='m_4.RData')
save(m.5, data, file='m_5.RData')
save(m.6, data, file='m_6.RData')
save(m.7, data, file='m_7.RData')
save(m.8, data, file='m_8.RData')
save(m.9, data, file='m_9.RData')

这是相关的错误消息:

Error in sendMaster(try(eval(expr, env), silent = TRUE)) : 
  long vectors not supported yet: fork.c:378
Calls: f_lmer_mc ... mclapply -> lapply -> FUN -> mcparallel -> sendMaster

谢谢!

更新:

该数据是公开可用的 European Social Survey 的清理版本。 。您可以从here下载该文件。 (1.8 MB)

Answer 1

我认为发生此错误是因为 fork 的工作进程在序列化非常大的结果对象时遇到错误。我已经能够使用以下代码在 R 3.3.2 中重现此错误:

library(parallel)
r <- mclapply(1:2, function(i) 1:2^30, mc.cores=2, mc.preschedule=FALSE)

但是，这个示例对我使用 R 3.4.3 的 64 位版本有效，因此序列化限制似乎在更高版本的 R 中已被删除(或至少增加)。

我建议您尝试将结果对象的大小减少到 2GB 以下，或者使用最新版本的 R。